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1,310 bytes added ,  21:49, December 30, 2008
added a list of simple integrals
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An '''indefinite integral''', or antiderivative, is an [[integral]] without upper and lower limits.
 
An '''indefinite integral''', or antiderivative, is an [[integral]] without upper and lower limits.
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There are an [[infinite]] number of antiderivatives for a given function, because each indefinite [[integral]] can have an arbitrary constant added to it which disappears upon integration.  However, the [[fundamental theorem of calculus]] relates a [[definite integral]] to an indefinite integral by taking its value at the boundary points.
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== See Also ==
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== Indefinite Integrals ==
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There are an [[infinite]] number of antiderivatives for a given function, because each indefinite [[integral]] can have an arbitrary constant added to it which disappears upon differentiation.  However, the [[fundamental theorem of calculus]] relates a [[definite integral]] to an indefinite integral by taking its value at the boundary points.
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Whenever any expression is integrated the constant of integration, <math>C</math>, is always added.
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== A list of simple antiderivatives ==
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The identity antiderivative:
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:<math>\int dx = x + C</math>
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=== Polynomial and simple rational ===
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:<math>\int xdx = {1 \over 2} x^2 + C</math>
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:<math>\int x^2dx = {1 \over 3} x^3 + C</math>
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:<math>\int {1 \over {x^3}}dx = \int x^{-3}dx = {1 \over -3}x^{-2} + C = {-1 \over {3x^{-2}}} + C</math>
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:<math>\int x^{3.873}dx = {1 \over 4.873} x^{4.873} + C</math>
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The general rule for polynomial expressions is:
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:<math>\int x^ndx = {1 \over {n+1}} x ^ {n + 1} + C</math>
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Note: <math>n \ne -1</math>.  See below for when <math>n=-1</math>
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=== Rational ===
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{{main|Partial fractions in integration}}
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Rational antiderivatives are much more difficult and follow different rules.
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: <math>\int {1 \over x}dx = \int x^{-1}dx = \ln(x) + C</math>
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: <math>\int {1 \over {x+1}}dx = \ln(x+1) + C</math>
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: <math>\int {1 \over {x+a}}dx = \ln(x+a) + C</math>
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=== Trigonometric ===
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:<math>\int \sin(x)dx = -\cos(x) + C</math>
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:<math>\int \cos(x)dx = \sin(x) + C</math>
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:<math>\int \tan(x)dx = \ln|\sec(x)| + C</math>
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:<math>\int \sin(x)dx = -\cos(x) + C</math>
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=== Exponential ===
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:<math>\int e^x = e^x + C</math>
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:<math>\int a^x = \ln(a)a^x + C</math>
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== See also ==
    
*[[Integral]]
 
*[[Integral]]
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