A single fraction with linear factors in the denominator can be split into two or more fractions, known as
partial fractions
There are three types:
- \(\dfrac{px+q}{(x+a)(x+b)}=\dfrac{A}{x+a}+\dfrac{B}{x+b}\)
- \(\dfrac{px^2+qx+r}{(x+a)(x+b)(x+c)}=\dfrac{A}{x+a}+\dfrac{B}{x+b}+\dfrac{C}{x+c}\)
- \(\dfrac{px^2+qx+r}{(x+a)(x+b)^2}=\dfrac{A}{x+a}+\dfrac{B}{x+b}+\dfrac{C}{(x+b)^2}\)
The constants \(A\), \(B\) and \(C\) can be found by either
substitution or
equating coefficients.
Partial fractions are used for integration and binomial expansions.
There are three types of partial fractions:
- \(\dfrac{px+q}{(x+a)(x+b)}=\dfrac{A}{x+a}+\dfrac{B}{x+b}\)
- \(\dfrac{px^2+qx+r}{(x+a)(x+b)(x+c)}=\dfrac{A}{x+a}+\dfrac{B}{x+b}+\dfrac{C}{x+c}\)
- \(\dfrac{px^2+qx+r}{(x+a)(x+b)^2}=\dfrac{A}{x+a}+\dfrac{B}{x+b}+\dfrac{C}{(x+b)^2}\)
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