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Wikipedia / Differentiation rules

This article is a summary of differentiation rules, that is, rules for computing the derivative of a function in calculus.

Elementary rules of differentiation

Unless otherwise stated, all functions are functions of real numbers) that return real values, although, more generally, the formulas below apply wherever they are well defined, including the case of complex numbers).

Constant term rule

.

Proof

This computation shows that the derivative of any constant function is 0.

Intuitive (geometric) explanation

The derivative of the function at a point is the slope of the line tangent to the curve at the point. The slope of the constant function is 0, because the tangent line to the constant function is horizontal and its angle is 0.

increases or decreases.

Linearity of differentiation

.

In Leibniz's notation

Special cases include:

  • The constant factor rule:

    The sum rule:

    The difference rule:

Product rule

Chain rule

Inverse function rule

has an inverse function

Power laws, polynomials, quotients, and reciprocals

Polynomial or elementary power rule

.

Combining the power rule with the sum and constant multiple rules permits the computation of the derivative of any polynomial.

Reciprocal rule

is nonzero.

The reciprocal rule can be derived either from the quotient rule or from the combination of power rule and chain rule.

Quotient rule

is nonzero.

This can be derived from the product rule and the reciprocal rule.

Generalized power rule

The elementary power rule generalizes considerably. The most general power rule is the functional power rule wherever both sides are well defined.

Special cases:

  • is positive.

  • .

Derivatives of exponential and logarithmic functions

yields a complex number.

.

is the Lambert W function.

Logarithmic derivatives

The logarithmic derivative is another way of stating the rule for differentiating the logarithm is positive.

Logarithmic differentiation is a technique which uses logarithms and its differentiation rules to simplify certain expressions before actually applying the derivative.

Logarithms can be used to remove exponents, convert products into sums, and convert division into subtraction—each of which may lead to a simplified expression for taking derivatives.

Derivatives of trigonometric functions

.

It is common to additionally define an inverse tangent function with two arguments

Derivatives of hyperbolic functions

Derivatives of special functions

Gamma function

being the digamma function in the line above.

Riemann zeta function

Derivatives of integrals

This formula is the general form of the Leibniz integral rule and can be derived using the fundamental theorem of calculus.

Derivatives to nth order

is a positive integer, including:

Faà di Bruno's formula

consists of all non-negative integer solutions of the Diophantine equation.

General Leibniz rule

See also

References

Sources and further reading

These rules are given in many books, both on elementary and advanced calculus, in pure and applied mathematics. Those in this article (in addition to the above references) can be found in:

  • Mathematical Handbook of Formulas and Tables (3rd edition), S. Lipschutz, M.R. Spiegel, J. Liu, Schaum's Outline Series, 2009, .

  • The Cambridge Handbook of Physics Formulas, G. Woan, Cambridge University Press, 2010, .

  • Mathematical methods for physics and engineering, K.F. Riley, M.P. Hobson, S.J. Bence, Cambridge University Press, 2010,

  • NIST Handbook of Mathematical Functions, F. W. J. Olver, D. W. Lozier, R. F. Boisvert, C. W. Clark, Cambridge University Press, 2010, .