Calculus Examples

$\cos^{5} (π)$

Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cosine is negative in the second quadrant.

${(- \cos (0))}^{5}$

The exact value of $\cos (0)$ is $1$ .

${(- 1 \cdot 1)}^{5}$

Multiply $- 1$ by $1$ .

${(- 1)}^{5}$

Raise $- 1$ to the power of $5$ .

$- 1$