### Home > CALC > Chapter 9 > Lesson 9.1.1 > Problem 9-9

9-9.

Graph the function. What do you notice?

Use partial fraction decomposition to rewrite the integrand as a sum of fractions.

Use substitution.

Let *u* = cos^{–1}(*x*). Then *du* = _____.

Recall that cos^{2}(*x*) – sin^{2}(*x*) = cos(2*x*).