Primitive of Arccosine Function

Theorem

 * $\ds \int \arccos x \rd x = x \arccos x - \sqrt {1 - x^2} + C$

Proof
From Primitive of $\arccos \dfrac x a$:
 * $\ds \int \arccos \frac x a \rd x = x \arccos \frac x a - \sqrt {a^2 - x^2} + C$

The result follows by setting $a = 1$.

Also see

 * Primitive of $\arcsin x$
 * Primitive of $\arctan x$
 * Primitive of $\arccot x$