6. Analytic Trigonometry

Use the even-odd identities to evaluate the expression.

$\cos (-\theta )-\cos \theta$

Use the even-odd identities to evaluate the expression.

$-\cot \left(\theta \right)\cdot \sin (-\theta )$

Select the expression with the same value as the given expression.

$\sec (-\frac{4\pi }{5})$

Select the expression with the same value as the given expression.

$\sin (-38°)$