Primitive of Reciprocal of a x + b cubed/Proof 2
Jump to navigation
Jump to search
Theorem
- $\ds \int \frac {\d x} {\paren {a x + b}^3} = -\frac 1 {2 a \paren {a x + b}^2} + C$
Proof
From Primitive of Power of $a x + b$:
- $\ds \int \paren {a x + b}^n \rd x = \frac {\paren {a x + b}^{n + 1} } {\paren {n + 1} a} + C$
where $n \ne 1$.
The result follows by setting $n = -3$.
$\blacksquare$