Techniques of integration: Partial Fractions: Distinct Linear Factors: Find ![]()
We shall decompose the fraction, F, in the integrand by factoring and rewriting it as partial fractions:
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We can determine A and B by combining the terms on the right hand side:
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We know that this can be satisfied by all values of x, and that the numerators must be equal.
In particular, we can use convenient values of x: -3 and +4.
Try
. Then
, or
, or ![]()
Now try
:
, or
, or ![]()
Now we can substitute these values into the original fraction, F:
, and accordingly, the original integral becomes
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With
,
;
,
, we get
. We can use the integral leading to the natural log:
. As a final step, we convert back to expressions in x:
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