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Differentiation rules 1 Differentiation rules This 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 will be functions from R to R, although more generally, the formulae below make sense wherever they are well defined. Differentiation is linear For any functions f and g and any real numbers a and b. In other words, the derivative of the function h(x) = a f(x) + b g(x) with respect to x is In Leibniz's notation this is written Special cases include: The constant multiple rule The sum rule The subtraction rule The product or Leibniz rule For any of the functions f and g, In other words, the derivative of the function h(x) = f(x) g(x) with respect to x is In Leibniz's notation this is written

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Page 1: maths 3 diffrentiation rule

Differentiation rules 1

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

Elementary rules of differentiationUnless otherwise stated, all functions will be functions from R to R, although more generally, the formulae belowmake sense wherever they are well defined.

Differentiation is linearFor any functions f and g and any real numbers a and b.

In other words, the derivative of the function h(x) = a f(x) + b g(x) with respect to x is

In Leibniz's notation this is written

Special cases include:• The constant multiple rule

• The sum rule

• The subtraction rule

The product or Leibniz ruleFor any of the functions f and g,

In other words, the derivative of the function h(x) = f(x) g(x) with respect to x is

In Leibniz's notation this is written

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Differentiation rules 2

The chain rule

This is a rule for computing the derivative of a function of a function, i.e., of the composite of two functions fand g:

In other words, the derivative of the function h(x) = f(g(x)) with respect to x is

In Leibniz's notation this is written (suggestively) as:

The polynomial or elementary power rule

If , for some natural number n (including zero) then

Special cases include:• Constant rule: if f is the constant function f(x) = c, for any number c, then for all x

• The derivative of a linear function is constant: if f(x) = ax (or more generally, in view of the constant rule, iff(x)=ax+b ), then

Combining this rule with the linearity of the derivative permits the computation of the derivative of any polynomial.

The reciprocal ruleFor any (nonvanishing) function f, the derivative of the function 1/f (equal at x to 1/f(x)) is

In other words, the derivative of h(x) = 1/f(x) is

In Leibniz's notation, this is written

The inverse function ruleThis should not be confused with the reciprocal rule: the reciprocal 1/x of a nonzero real number x is its inverse withrespect to multiplication, whereas the inverse of a function is its inverse with respect to function composition.If the function f has an inverse g = f−1 (so that g(f(x)) = x and f(g(y)) = y) then

In Leibniz notation, this is written (suggestively) as

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Differentiation rules 3

Further rules of differentiation

The quotient ruleIf f and g are functions, then:

wherever g is nonzero.

This can be derived from reciprocal rule and the product rule. Conversely (using the constant rule) the reciprocal ruleis the special case f(x) = 1.

Generalized power ruleThe elementary power rule generalizes considerably. First, if x is positive, it holds when n is any real number. Thereciprocal rule is then the special case n = -1 (although care must then be taken to avoid confusion with the inverserule).The most general power rule is the functional power rule: for any functions f and g,

wherever both sides are well defined.

Logarithmic derivativesThe logarithmic derivative is another way of stating the rule for differentiating the logarithm of a function (using thechain rule):

wherever f is positive.

Derivatives of exponential and logarithmic functions

note that the equation above is true for all c, but the derivative for c < 0 yields a complex number.

the equation above is also true for all c but yields a complex number.

The derivative of the natural logarithm with a generalised functional argument f(x) is

By applying the change-of-base rule, the derivative for other bases is

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Differentiation rules 4

Derivatives of trigonometric functions

Derivatives of hyperbolic functions

Derivatives of special functions

Gamma function

Riemann Zeta function

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Differentiation rules 5

Nth DerivativesThe following formulae can be obtained empirically by repeated differentiation and taking notice of patterns; eitherby hand or computed by a CAS (Computer Algebra System).[1] Below y is the dependent variable, x is theindependent variable, real number constants are A, B, N, r, real integers are n and j, F(x) is a continuouslydifferentiable function (the nth derivative exists), and i is the imaginary unit .

Function nth Derivative

where

and the set consists of all non-negative integer solutions of the Diophantine equation

See: Expansions for nearly Gaussian distributions by S. Blinnikov and R. Moessner [2]

For the case of (the

exponential function),the above reduces to:

where is the Kronecker delta.

Expanding this by the sine addition formula yields a more clear form to use:

Expanding by the cosine addition formula:

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Differentiation rules 6

References[1] http:/ / www. wolframalpha. com/ input/ ?i=nth+ derivative+ of+ %5Bf%28x%29%5D%5Er[2] http:/ / aas. aanda. org/ index. php?option=com_article& access=standard& Itemid=129& url=/ articles/ aas/ pdf/ 1998/ 10/ h0596. pdf

External LinksDerivative calculator with formula simplification (http:/ / www. planetcalc. com/ 675/ )• A Table of Derivatives (http:/ / mathmajor. org/ home/ calculus-and-analysis/ table-of-derivatives/ )

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Article Sources and Contributors 7

Article Sources and ContributorsDifferentiation rules  Source: http://en.wikipedia.org/w/index.php?oldid=443085242  Contributors: Ace Frahm, Aeonx, Blackknight12, Bo Jacoby, Bobbo, Bongwarrior, Chris G, Chrishmt0423,Dondegroovily, El4mo, Foxjwill, Geometry guy, JLM, Jameshales, Jsnx, KDesk, KimvdLinde, Lowellian, Maschen, McVities, N5iln, Oleg Alexandrov, PV=nRT, Personline, Qwertyus, Ricardosandoval, Shadowjams, Skarebo, Smoken Flames, Tedder, Zmoney918, 37 anonymous edits

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