The derivative is a fundamental tool of calculus that quantifies the sensitivity of change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is the slope of the tangent line to the graph of the function at that point. The tangent line is the best linear approximation of the function near that input value. For this reason, the derivative is often described as the instantaneous rate of change, the ratio of the instantaneous change in the dependent variable to that of the independent variable.[1] The process of finding a derivative is called differentiation.

There are multiple different notations for differentiation, two of the most commonly used being Leibniz notation and prime notation. Leibniz notation, named after Gottfried Wilhelm Leibniz, is represented as the ratio of two differentials, whereas prime notation is written by adding a prime mark. Higher order notations represent repeated differentiation, and they are usually denoted in Leibniz notation by adding superscripts to the differentials, and in prime notation by adding additional prime marks. The higher order derivatives can be applied in physics; for example, while the first derivative of the position of a moving object with respect to time is the object's velocity, how the position changes as time advances, the second derivative is the object's acceleration, how the velocity changes as time advances.

Derivatives can be generalized to functions of several real variables. In this generalization, the derivative is reinterpreted as a linear transformation whose graph is (after an appropriate translation) the best linear approximation to the graph of the original function. The Jacobian matrix is the matrix that represents this linear transformation with respect to the basis given by the choice of independent and dependent variables. It can be calculated in terms of the partial derivatives with respect to the independent variables. For a real-valued function of several variables, the Jacobian matrix reduces to the gradient vector.

Definition edit

As a limit edit

A function of a real variable   is differentiable at a point   of its domain, if its domain contains an open interval containing  , and the limit

exists.[2] This means that, for every positive real number  , there exists a positive real number   such that, for every   such that   and   then   is defined, and
where the vertical bars denote the absolute value. This is an example of the (ε, δ)-definition of limit.[3]

If the function   is differentiable at  , that is if the limit   exists, then this limit is called the derivative of   at  . Multiple notations for the derivative exist.[4] The derivative of   at   can be denoted  , read as "  prime of  "; or it can be denoted  , read as "the derivative of   with respect to   at  " or "  by (or over)   at  ". See § Notation below. If   is a function that has a derivative at every point in its domain, then a function can be defined by mapping every point   to the value of the derivative of   at  . This function is written   and is called the derivative function or the derivative of  . The function   sometimes has a derivative at most, but not all, points of its domain. The function whose value at   equals   whenever   is defined and elsewhere is undefined is also called the derivative of  . It is still a function, but its domain may be smaller than the domain of  .[5]

For example, let   be the squaring function:  . Then the quotient in the definition of the derivative is[6]

The division in the last step is valid as long as  . The closer   is to  , the closer this expression becomes to the value  . The limit exists, and for every input   the limit is  . So, the derivative of the squaring function is the doubling function:  .
The graph of a function, drawn in black, and a tangent line to that graph, drawn in red. The slope of the tangent line is equal to the derivative of the function at the marked point.
The derivative at different points of a differentiable function. In this case, the derivative is equal to  

The ratio in the definition of the derivative is the slope of the line through two points on the graph of the function  , specifically the points   and  . As   is made smaller, these points grow closer together, and the slope of this line approaches the limiting value, the slope of the tangent to the graph of   at  . In other words, the derivative is the slope of the tangent.[7]

Using infinitesimals edit

One way to think of the derivative   is as the ratio of an infinitesimal change in the output of the function   to an infinitesimal change in its input.[8] In order to make this intuition rigorous, a system of rules for manipulating infinitesimal quantities is required.[9] The system of hyperreal numbers is a way of treating infinite and infinitesimal quantities. The hyperreals are an extension of the real numbers that contain numbers greater than anything of the form   for any finite number of terms. Such numbers are infinite, and their reciprocals are infinitesimals. The application of hyperreal numbers to the foundations of calculus is called nonstandard analysis. This provides a way to define the basic concepts of calculus such as the derivative and integral in terms of infinitesimals, thereby giving a precise meaning to the   in the Leibniz notation. Thus, the derivative of   becomes

for an arbitrary infinitesimal  , where   denotes the standard part function, which "rounds off" each finite hyperreal to the nearest real.[10] Taking the squaring function   as an example again,

Continuity and differentiability edit

This function does not have a derivative at the marked point, as the function is not continuous there (specifically, it has a jump discontinuity).
The absolute value function is continuous but fails to be differentiable at x = 0 since the tangent slopes do not approach the same value from the left as they do from the right.

If   is differentiable at  , then   must also be continuous at  .[11] As an example, choose a point   and let   be the step function that returns the value 1 for all   less than  , and returns a different value 10 for all   greater than or equal to  . The function   cannot have a derivative at  . If   is negative, then   is on the low part of the step, so the secant line from   to   is very steep; as   tends to zero, the slope tends to infinity. If   is positive, then   is on the high part of the step, so the secant line from   to   has slope zero. Consequently, the secant lines do not approach any single slope, so the limit of the difference quotient does not exist. However, even if a function is continuous at a point, it may not be differentiable there. For example, the absolute value function given by   is continuous at  , but it is not differentiable there. If   is positive, then the slope of the secant line from 0 to   is one; if   is negative, then the slope of the secant line from   to   is  .[12] This can be seen graphically as a "kink" or a "cusp" in the graph at  . Even a function with a smooth graph is not differentiable at a point where its tangent is vertical: For instance, the function given by   is not differentiable at  . In summary, a function that has a derivative is continuous, but there are continuous functions that do not have a derivative.[11]

Most functions that occur in practice have derivatives at all points or almost every point. Early in the history of calculus, many mathematicians assumed that a continuous function was differentiable at most points.[13] Under mild conditions (for example, if the function is a monotone or a Lipschitz function), this is true. However, in 1872, Weierstrass found the first example of a function that is continuous everywhere but differentiable nowhere. This example is now known as the Weierstrass function.[14] In 1931, Stefan Banach proved that the set of functions that have a derivative at some point is a meager set in the space of all continuous functions. Informally, this means that hardly any random continuous functions have a derivative at even one point.[15]

Notation edit

One common symbol for the derivative of a function is Leibniz notation. They are written as the quotient of two differentials   and  ,[16] which were introduced by Gottfried Wilhelm Leibniz in 1675.[17] It is still commonly used when the equation   is viewed as a functional relationship between dependent and independent variables. The first derivative is denoted by  , read as "the derivative of   with respect to  ".[18] This derivative can alternately be treated as the application of a differential operator to a function,   Higher derivatives are expressed using the notation   for the  -th derivative of  . These are abbreviations for multiple applications of the derivative operator; for example,  [19] Unlike some alternatives, Leibniz notation involves explicit specification of the variable for differentiation, in the denominator, which removes ambiguity when working with multiple interrelated quantities. The derivative of a composed function can be expressed using the chain rule: if   and   then  [20]

Another common notation for differentiation is by using the prime mark in the symbol of a function  . This is known as prime notation, due to Joseph-Louis Lagrange.[21] The first derivative is written as  , read as "  prime of  ", or  , read as "  prime".[22] Similarly, the second and the third derivatives can be written as   and  , respectively.[23] For denoting the number of higher derivatives beyond this point, some authors use Roman numerals in superscript, whereas others place the number in parentheses, such as   or  [24] The latter notation generalizes to yield the notation   for the  -th derivative of  .[19]

In Newton's notation or the dot notation, a dot is placed over a symbol to represent a time derivative. If   is a function of  , then the first and second derivatives can be written as   and  , respectively. This notation is used exclusively for derivatives with respect to time or arc length. It is typically used in differential equations in physics and differential geometry.[25] However, the dot notation becomes unmanageable for high-order derivatives (of order 4 or more) and cannot deal with multiple independent variables.

Another notation is D-notation, which represents the differential operator by the symbol  [19] The first derivative is written   and higher derivatives are written with a superscript, so the  -th derivative is   This notation is sometimes called Euler notation, although it seems that Leonhard Euler did not use it, and the notation was introduced by Louis François Antoine Arbogast.[26] To indicate a partial derivative, the variable differentiated by is indicated with a subscript, for example given the function   its partial derivative with respect to   can be written   or   Higher partial derivatives can be indicated by superscripts or multiple subscripts, e.g.   and  .[27]

Rules of computation edit

In principle, the derivative of a function can be computed from the definition by considering the difference quotient and computing its limit. Once the derivatives of a few simple functions are known, the derivatives of other functions are more easily computed using rules for obtaining derivatives of more complicated functions from simpler ones. This process of finding a derivative is known as differentiation.[28]

Rules for basic functions edit

The following are the rules for the derivatives of the most common basic functions. Here,   is a real number, and   is the mathematical constant approximately 2.71828.[29]

  • Derivatives of powers:
  • Functions of exponential, natural logarithm, and logarithm with general base:
     , for  
     , for  
     , for  
  • Trigonometric functions:
  • Inverse trigonometric functions:
     , for  
     , for  

Rules for combined functions edit

Given that the   and   are the functions. The following are some of the most basic rules for deducing the derivative of functions from derivatives of basic functions.[30]

  • Constant rule: if   is constant, then for all  ,
  • Sum rule:
      for all functions   and   and all real numbers   and  .
  • Product rule:
      for all functions   and  . As a special case, this rule includes the fact   whenever   is a constant because   by the constant rule.
  • Quotient rule:
      for all functions   and   at all inputs where g ≠ 0.
  • Chain rule for composite functions: If  , then

Computation example edit

The derivative of the function given by   is

Here the second term was computed using the chain rule and the third term using the product rule. The known derivatives of the elementary functions  ,  ,  ,  , and  , as well as the constant  , were also used.

Higher-order derivatives edit

Higher order derivatives means that a function is differentiated repeatedly. Given that   is a differentiable function, the derivative of   is the first derivative, denoted as  . The derivative of   is the second derivative, denoted as  , and the derivative of   is the third derivative, denoted as  . By continuing this process, if it exists, the  -th derivative as the derivative of the  -th derivative or the derivative of order  . As has been discussed above, the generalization of derivative of a function   may be denoted as  .[31] A function that has   successive derivatives is called   times differentiable. If the  -th derivative is continuous, then the function is said to be of differentiability class  .[32] A function that has infinitely many derivatives is called infinitely differentiable or smooth.[33] One example of the infinitely differentiable function is polynomial; differentiate this function repeatedly results the constant function, and the infinitely subsequent derivative of that function are all zero.[34]

In one of its applications, the higher-order derivatives may have specific interpretations in physics. Suppose that a function represents the position of an object at the time. The first derivative of that function is the velocity of an object with respect to time, the second derivative of the function is the acceleration of an object with respect to time,[28] and the third derivative is the jerk.[35]

In other dimensions edit

Vector-valued functions edit

A vector-valued function   of a real variable sends real numbers to vectors in some vector space  . A vector-valued function can be split up into its coordinate functions  , meaning that  . This includes, for example, parametric curves in   or  . The coordinate functions are real-valued functions, so the above definition of derivative applies to them. The derivative of   is defined to be the vector, called the tangent vector, whose coordinates are the derivatives of the coordinate functions. That is,[36]

if the limit exists. The subtraction in the numerator is the subtraction of vectors, not scalars. If the derivative of   exists for every value of  , then   is another vector-valued function.[36]

Partial derivatives edit

Functions can depend upon more than one variable. A partial derivative of a function of several variables is its derivative with respect to one of those variables, with the others held constant. Partial derivatives are used in vector calculus and differential geometry. As with ordinary derivatives, multiple notations exist: the partial derivative of a function   with respect to the variable   is variously denoted by

 ,  ,  ,  , or  ,

among other possibilities.[37] It can be thought of as the rate of change of the function in the  -direction.[38] Here is a rounded d called the partial derivative symbol. To distinguish it from the letter d, ∂ is sometimes pronounced "der", "del", or "partial" instead of "dee".[39] For example, let  , then the partial derivative of function   with respect to both variables   and   are, respectively:

In general, the partial derivative of a function   in the direction   at the point   is defined to be:[40]

This is fundamental for the study of the functions of several real variables. Let   be such a real-valued function. If all partial derivatives   with respect to   are defined at the point  , these partial derivatives define the vector

which is called the gradient of   at  . If   is differentiable at every point in some domain, then the gradient is a vector-valued function   that maps the point   to the vector  . Consequently, the gradient determines a vector field.[41]

Directional derivatives edit

If   is a real-valued function on  , then the partial derivatives of   measure its variation in the direction of the coordinate axes. For example, if   is a function of   and  , then its partial derivatives measure the variation in   in the   and   direction. However, they do not directly measure the variation of   in any other direction, such as along the diagonal line  . These are measured using directional derivatives. Choose a vector  , then the directional derivative of   in the direction of   at the point   is:[42]


If all the partial derivatives of   exist and are continuous at  , then they determine the directional derivative of   in the direction   by the formula:[43]


Total derivative, total differential and Jacobian matrix edit

When   is a function from an open subset of   to  , then the directional derivative of   in a chosen direction is the best linear approximation to   at that point and in that direction. However, when  , no single directional derivative can give a complete picture of the behavior of  . The total derivative gives a complete picture by considering all directions at once. That is, for any vector   starting at  , the linear approximation formula holds:[44]

Similarly with the single-variable derivative,   is chosen so that the error in this approximation is as small as possible. The total derivative of   at   is the unique linear transformation   such that[44]
Here   is a vector in  , so the norm in the denominator is the standard length on  . However,   is a vector in  , and the norm in the numerator is the standard length on  .[44] If   is a vector starting at  , then   is called the pushforward of   by  .[45]

If the total derivative exists at  , then all the partial derivatives and directional derivatives of   exist at  , and for all  ,   is the directional derivative of   in the direction  . If   is written using coordinate functions, so that  , then the total derivative can be expressed using the partial derivatives as a matrix. This matrix is called the Jacobian matrix of   at  :[46]


Generalizations edit

The concept of a derivative can be extended to many other settings. The common thread is that the derivative of a function at a point serves as a linear approximation of the function at that point.

  • An important generalization of the derivative concerns complex functions of complex variables, such as functions from (a domain in) the complex numbers   to  . The notion of the derivative of such a function is obtained by replacing real variables with complex variables in the definition.[47] If   is identified with   by writing a complex number   as  , then a differentiable function from   to   is certainly differentiable as a function from   to   (in the sense that its partial derivatives all exist), but the converse is not true in general: the complex derivative only exists if the real derivative is complex linear and this imposes relations between the partial derivatives called the Cauchy–Riemann equations – see holomorphic functions.[48]
  • Another generalization concerns functions between differentiable or smooth manifolds. Intuitively speaking such a manifold   is a space that can be approximated near each point   by a vector space called its tangent space: the prototypical example is a smooth surface in  . The derivative (or differential) of a (differentiable) map   between manifolds, at a point   in  , is then a linear map from the tangent space of   at   to the tangent space of   at  . The derivative function becomes a map between the tangent bundles of   and  . This definition is used in differential geometry.[49]
  • Differentiation can also be defined for maps between vector space, such as Banach space, in which those generalizations are the Gateaux derivative and the Fréchet derivative.[50]
  • One deficiency of the classical derivative is that very many functions are not differentiable. Nevertheless, there is a way of extending the notion of the derivative so that all continuous functions and many other functions can be differentiated using a concept known as the weak derivative. The idea is to embed the continuous functions in a larger space called the space of distributions and only require that a function is differentiable "on average".[51]
  • Properties of the derivative have inspired the introduction and study of many similar objects in algebra and topology; an example is differential algebra. Here, it consists of the derivation of some topics in abstract algebra, such as rings, ideals, field, and so on.[52]
  • The discrete equivalent of differentiation is finite differences. The study of differential calculus is unified with the calculus of finite differences in time scale calculus.[53]
  • The arithmetic derivative involves the function that is defined for the integers by the prime factorization. This is an analogy with the product rule.[54]

See also edit

Notes edit

  1. ^ Stewart 2002, p. 129–130.
  2. ^ Stewart 2002, p. 127; Strang et al. 2023, p. 220.
  3. ^ Gonick 2012, p. 83.
  4. ^ Gonick 2012, p. 88; Strang et al. 2023, p. 234.
  5. ^ Gonick 2012, p. 83; Strang et al. 2023, p. 232.
  6. ^ Gonick 2012, pp. 77–80.
  7. ^ Thompson 1998, pp. 34, 104; Stewart 2002, p. 128.
  8. ^ Thompson 1998, pp. 84–85.
  9. ^ Keisler 2012, pp. 902–904.
  10. ^ Keisler 2012, p. 45; Henle & Kleinberg 2003, p. 66.
  11. ^ a b Gonick 2012, p. 156.
  12. ^ Gonick 2012, p. 149.
  13. ^ Jašek 1922; Jarník 1922; Rychlík 1923.
  14. ^ David 2018.
  15. ^ Banach 1931, cited in Hewitt & Stromberg 1965.
  16. ^ Apostol 1967, p. 172.
  17. ^ Cajori 2007, p. 204.
  18. ^ Moore & Siegel 2013, p. 110.
  19. ^ a b c Varberg, Purcell & Rigdon 2007, p. 125–126.
  20. ^ In the formulation of calculus in terms of limits, various authors have assigned the   symbol various meanings. Some authors such as Varberg, Purcell & Rigdon 2007, p. 119 and Stewart 2002, p. 177 do not assign a meaning to   by itself, but only as part of the symbol  . Others define   as an independent variable, and define   by
    In non-standard analysis   is defined as an infinitesimal. It is also interpreted as the exterior derivative of a function  . See differential (infinitesimal) for further information.
  21. ^ Schwartzman 1994, p. 171.
  22. ^ Moore & Siegel 2013, p. 110; Goodman 1963, p. 78–79.
  23. ^ Varberg, Purcell & Rigdon 2007, p. 125–126; Cajori 2007, p. 228.
  24. ^ Choudary & Niculescu 2014, p. 222; Apostol 1967, p. 171.
  25. ^ Evans 1999, p. 63; Kreyszig 1991, p. 1.
  26. ^ Cajori 1923.
  27. ^ Apostol 1967, p. 172; Varberg, Purcell & Rigdon 2007, p. 125–126.
  28. ^ a b Apostol 1967, p. 160.
  29. ^ Varberg, Purcell & Rigdon 2007. See p. 133 for the power rule, p. 115–116 for the trigonometric functions, p. 326 for the natural logarithm, p. 338–339 for exponential with base  , p. 343 for the exponential with base  , p. 344 for the logarithm with base  , and p. 369 for the inverse of trigonometric functions.
  30. ^ For constant rule and sum rule, see Apostol 1967, p. 161, 164, respectively. For the product rule, quotient rule, and chain rule, see Varberg, Purcell & Rigdon 2007, p. 111–112, 119, respectively. For the special case of the product rule, that is, the product of a constant and a function, see Varberg, Purcell & Rigdon 2007, p. 108–109.
  31. ^ Apostol 1967, p. 160; Varberg, Purcell & Rigdon 2007, p. 125–126.
  32. ^ Warner 1983, p. 5.
  33. ^ Debnath & Shah 2015, p. 40.
  34. ^ Carothers 2000, p. 176.
  35. ^ Stewart 2002, p. 193.
  36. ^ a b Stewart 2002, p. 893.
  37. ^ Stewart 2002, p. 947; Christopher 2013, p. 682.
  38. ^ Stewart 2002, p. 949.
  39. ^ Silverman 1989, p. 216; Bhardwaj 2005, See p. 6.4.
  40. ^ Mathai & Haubold 2017, p. 52.
  41. ^ Gbur 2011, pp. 36–37.
  42. ^ Varberg, Purcell & Rigdon 2007, p. 642.
  43. ^ Guzman 2003, p. 35.
  44. ^ a b c Davvaz 2023, p. 266.
  45. ^ Lee 2013, p. 72.
  46. ^ Davvaz 2023, p. 267.
  47. ^ Roussos 2014, p. 303.
  48. ^ Gbur 2011, pp. 261–264.
  49. ^ Gray, Abbena & Salamon 2006, p. 826.
  50. ^ Azegami 2020. See p. 209 for the Gateaux derivative, and p. 211 for the Fréchet derivative.
  51. ^ Funaro 1992, p. 84–85.
  52. ^ Kolchin 1973, p. 58, 126.
  53. ^ Georgiev 2018, p. 8.
  54. ^ Barbeau 1961.

References edit

  • Apostol, Tom M. (June 1967), Calculus, Vol. 1: One-Variable Calculus with an Introduction to Linear Algebra, vol. 1 (2nd ed.), Wiley, ISBN 978-0-471-00005-1
  • Azegami, Hideyuki (2020), Shape Optimization Problems, Springer Optimization and Its Applications, vol. 164, Springer, doi:10.1007/978-981-15-7618-8, ISBN 978-981-15-7618-8, S2CID 226442409
  • Banach, Stefan (1931), "Uber die Baire'sche Kategorie gewisser Funktionenmengen", Studia Math., 3 (3): 174–179, doi:10.4064/sm-3-1-174-179.
  • Barbeau, E. J. (1961). "Remarks on an arithmetic derivative". Canadian Mathematical Bulletin. 4 (2): 117–122. doi:10.4153/CMB-1961-013-0. Zbl 0101.03702.
  • Bhardwaj, R. S. (2005), Mathematics for Economics & Business (2nd ed.), Excel Books India, ISBN 9788174464507
  • Cajori, Florian (1923), "The History of Notations of the Calculus", Annals of Mathematics, 25 (1): 1–46, doi:10.2307/1967725, hdl:2027/mdp.39015017345896, JSTOR 1967725
  • Cajori, Florian (2007), A History of Mathematical Notations, vol. 2, Cosimo Classics, ISBN 978-1-60206-713-4
  • Carothers, N. L. (2000), Real Analysis, Cambridge University Press
  • Choudary, A. D. R.; Niculescu, Constantin P. (2014), Real Analysis on Intervals, Springer India, doi:10.1007/978-81-322-2148-7, ISBN 978-81-322-2148-7
  • Christopher, Essex (2013), Calculus: A complete course, Pearson, p. 682, ISBN 9780321781079, OCLC 872345701
  • Courant, Richard; John, Fritz (December 22, 1998), Introduction to Calculus and Analysis, Vol. 1, Springer-Verlag, doi:10.1007/978-1-4613-8955-2, ISBN 978-3-540-65058-4
  • David, Claire (2018), "Bypassing dynamical systems: A simple way to get the box-counting dimension of the graph of the Weierstrass function", Proceedings of the International Geometry Center, 11 (2), Academy of Sciences of Ukraine: 53–68, arXiv:1711.10349, doi:10.15673/tmgc.v11i2.1028
  • Davvaz, Bijan (2023), Vectors and Functions of Several Variables, Springer, doi:10.1007/978-981-99-2935-1, ISBN 978-981-99-2935-1, S2CID 259885793
  • Debnath, Lokenath; Shah, Firdous Ahmad (2015), Wavelet Transforms and Their Applications (2nd ed.), Birkhäuser, doi:10.1007/978-0-8176-8418-1, ISBN 978-0-8176-8418-1
  • Evans, Lawrence (1999), Partial Differential Equations, American Mathematical Society, ISBN 0-8218-0772-2
  • Eves, Howard (January 2, 1990), An Introduction to the History of Mathematics (6th ed.), Brooks Cole, ISBN 978-0-03-029558-4
  • Funaro, Daniele (1992), Polynomial Approximation of Differential Equations, Lecture Notes in Physics Monographs, vol. 8, Springer, doi:10.1007/978-3-540-46783-0, ISBN 978-3-540-46783-0
  • Gbur, Greg (2011), Mathematical Methods for Optical Physics and Engineering, Cambridge University Press,, ISBN 978-1-139-49269-0
  • Georgiev, Svetlin G. (2018), Fractional Dynamic Calculus and Fractional Dynamic Equations on Time Scales, Springer, doi:10.1007/978-3-319-73954-0, ISBN 978-3-319-73954-0
  • Goodman, A. W. (1963), Analytic Geometry and the Calculus, The MacMillan Company
  • Gonick, Larry (2012), The Cartoon Guide to Calculus, William Morrow, ISBN 978-0-06-168909-3
  • Gray, Alfred; Abbena, Elsa; Salamon, Simon (2006), Modern Differential Geometry of Curves and Surfaces with Mathematica, CRC Press, ISBN 978-1-58488-448-4
  • Guzman, Alberto (2003), Derivatives and Integrals of Multivariable Functions, Springer, doi:10.1007/978-1-4612-0035-2, ISBN 978-1-4612-0035-2
  • Henle, James M.; Kleinberg, Eugene M. (2003), Infinitesimal Calculus, Dover Publications, ISBN 978-0-486-42886-4
  • Hewitt, Edwin; Stromberg, Karl R. (1965), Real and abstract analysis, Springer-Verlag, Theorem 17.8, doi:10.1007/978-3-662-29794-0, ISBN 978-3-662-28275-5
  • Jašek, Martin (1922), "Funkce Bolzanova" (PDF), Časopis pro Pěstování Matematiky a Fyziky (in Czech), 51 (2): 69–76, doi:10.21136/CPMF.1922.121916
  • Jarník, Vojtěch (1922), "O funkci Bolzanově" (PDF), Časopis pro Pěstování Matematiky a Fyziky (in Czech), 51 (4): 248–264, doi:10.21136/CPMF.1922.109021. See the English version here.
  • Keisler, H. Jerome (2012) [1986], Elementary Calculus: An Approach Using Infinitesimals (2nd ed.), Prindle, Weber & Schmidt, ISBN 978-0-871-50911-6
  • Kolchin, Ellis (1973), Differential Algebra And Algebraic Groups, Academic Press, ISBN 978-0-08-087369-5
  • Kreyszig, Erwin (1991), Differential Geometry, New York: Dover, ISBN 0-486-66721-9
  • Larson, Ron; Hostetler, Robert P.; Edwards, Bruce H. (February 28, 2006), Calculus: Early Transcendental Functions (4th ed.), Houghton Mifflin Company, ISBN 978-0-618-60624-5
  • Lee, John M. (2013), Introduction to Smooth Manifolds, Graduate Texts in Mathematics, vol. 218, Springer, doi:10.1007/978-0-387-21752-9, ISBN 978-0-387-21752-9
  • Mathai, A. M.; Haubold, H. J. (2017), Fractional and Multivariable Calculus: Model Building and Optimization Problems, Springer, doi:10.1007/978-3-319-59993-9, ISBN 978-3-319-59993-9
  • Moore, Will H.; Siegel, David A. (2013), A Mathematical Course for Political and Social Research, Princeton University Press, ISBN 978-0-691-15995-9
  • Roussos, Ioannis M. (2014), Improper Riemann Integral, CRC Press, ISBN 978-1-4665-8807-3
  • Rychlík, Karel (1923), Über eine Funktion aus Bolzanos handschriftlichem Nachlasse
  • Schwartzman, Steven (1994), The Words of Mathematics: An Etymological Dictionary of Mathematical Terms Used in English, Mathematical Association of American, ISBN 9781614445012
  • Silverman, Richard A. (1989), Essential Calculus: With Applications, Courier Corporation, ISBN 9780486660974
  • Stewart, James (December 24, 2002), Calculus (5th ed.), Brooks Cole, ISBN 978-0-534-39339-7
  • Strang, Gilbert; et al. (2023), Calculus, volume 1, OpenStax, ISBN 978-1-947172-13-5
  • Thompson, Silvanus P. (September 8, 1998), Calculus Made Easy (Revised, Updated, Expanded ed.), New York: St. Martin's Press, ISBN 978-0-312-18548-0
  • Varberg, Dale E.; Purcell, Edwin J.; Rigdon, Steven E. (2007), Calculus (9th ed.), Pearson Prentice Hall, ISBN 978-0131469686
  • Warner, Frank W. (1983), Foundations of Differentiable Manifolds and Lie Groups, Springer, ISBN 978-0-387-90894-6

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