The graph of \( y=\cos \left(x+\frac{\pi}{2}\right) \) is the graph of the \( y=\cos (x) \) shifted in which direction? \( \frac{\pi}{2} \) units to the left \( \frac{\pi}{2} \) units to the right \( \frac{\pi}{2} \) units up \( \frac{\pi}{2} \) units down

Calcula la amplitud, el periodo y traza las gráficas: 7) \( y=\operatorname{sen}\left(\frac{x}{2}\right) \)

8) \( y=-3 \cos 2 x \) NOTA: Las gráficas deben de tener como mínimo un periodo.

- \( \left|\begin{array}{l}\text { 1.Решите уравнение. В ответе напишите } \\ \text { наименьший положительный корень. } \\ \sin \frac{\pi(x+9)}{4}=-1\end{array}\right| \)

b) \( 3\left(\cos ^{4} x+\sin ^{4} x\right)-2\left(\cos ^{6} x+\sin ^{6} x\right)=1 \)

The angle of depression from one mountain summit to another is \( 15.9^{\circ} \). If the two mountains differ in height by 430 metres, find the horizontal distance between the two summits, to the nearest centimetre.