1.1 KiB
1.1 KiB
Partial fraction decomposition is when you break a polynomial fraction down into smaller fractions that add together.
Degree where the numerator is less
- Factor the bottom.
- Create two fractions,
\frac{a}{p1}
, and\frac{b}{p2}
, where p1 and p2 are the polynomials you just factored out, and a/b are arbitrary variables - Multiply a by p2, and b by p1., giving you: $$\frac{ap2}{p1} + \frac{bp1}{p2}
- When you split the
Example
\frac{2x+1}{(x+1)(x+2)}
Given the above fraction, the denominator is already factored, so we can move onto the next step, where two fractions are made with a
and b
in the numerator, and each of the denominator components in the denominator:
\frac{a}{x+1} + \frac{b}{x+2}
Next, find a common denominator so that you can add the two fractions together. In this case, it's (x+1)(x+2)
.
Degree of the numerator is equal
- First perform polynomial division.
- Then find a partial fraction with the remainder
Degree where the numerator is greater
- First perform polynomial division to reach a point where the degree of the numerator is less than the degree of the denominator