If \( \theta=-\frac{\pi}{2} \), then find exact values for the following. If the trigonometric function is undefined for \( \theta=-\frac{\pi}{2} \), enter DNE \( \sec (\theta) \) equals DNE \( \csc (\theta) \) equals -1 \( \tan (\theta) \) equals DNE \( \cot (\theta) \) equals \( \square \sigma^{\circ} \)

\( \sin ^ { 2 } ( \alpha + \beta ) - \sin ^ { 2 } \alpha - \sin ^ { 2 } \beta \)

49. Hisoblang: \( 8 \cos \frac{\pi}{7} \cdot \cos \frac{4 \pi}{7} \cdot \cos \frac{5 \pi}{7} \) A) -1 B) 4 C) 1 D) 2

Which is the correct identity for cos? \( \cos \theta=\frac{h}{a} \) \( \cos =\frac{h}{a} \) \( \cos \theta=\frac{a}{h} \) \( \cos =\frac{a}{h} \)

If \( \theta=\frac{5 \pi}{6} \), then \( \cos (\theta)=\square \) \( \sin (\theta)=\square \) Give exact values. No decimals allowed!

\( \frac { 4 \sin \frac { \alpha } { 2 } \cos \frac { \alpha } { 2 } } { \tan \frac { \alpha } { 2 } } - 1 \)