Describe the graph of the function \( f(x)=\cos (2 x) \) as a transformation of its parent function. (1 point) The graph is a horizontal stretch by a factor of 2 . The graph is a vertical stretch by a factor of 2 . The graph is a horizontal compression by a factor of \( \frac{1}{2} \). The graph is a vertical compression by a factor of \( \frac{1}{2} \).

13. Calcule \( \sin \left(\frac{\pi}{4}\right) \)

13. Calcule \( \sin \left(\frac{\pi}{4}\right) \)

13. Obtenha as menores determinaçőes não negativas dos arcos. a) \( 1300^{\circ} \) b) \( 1440^{\circ} \) c) \( 170^{\circ} \) d) \( \frac{11 \pi}{2} \mathrm{rad} \) min e) \( \frac{43 \pi}{5} \mathrm{rad} \) f) \( -1200^{\circ} \)

Determine las soluciones en \( \mathbb{R} \) de la siguiente ecuación trigonométrica: \[ \sec ^{2}(x)-\sec (x)-2=0 \] a. \( S=\left\{\frac{\pi}{3}+2 k \pi, \frac{5 \pi}{3}+2 k \pi,(2 k+1) \pi: k \in \mathbb{Z}\right\} \) b. \( S=\left\{2 k \pi, \frac{2 \pi}{3}+2 k \pi, \frac{\pi}{6}+2 k \pi: k \in \mathbb{Z}\right\} \) c. \( S=\left\{k \pi, \frac{\pi}{6}+2 k \pi, \frac{5 \pi}{6}+2 k \pi \quad: \quad k \in \mathbb{Z}\right\} \) d. Ninguna de las anteriores

\( \frac { \cos x + \cot x } { 1 \operatorname { can } x + \sec x } = \cos x - \sin x \)