Search problems

3 problems match “cofunction identities”. Clear

Visitors search a sample. Sign in for free to search every problem. Sign in

1. Difference of squared sine and cosine ●○○○○ 10 ptsEvaluate $(\sin 72^\circ + \cos 18^\circ)(\sin 72^\circ - \cos 18^\circ)$.
2. Cosine shifted by 3π/2 from a terminal side ●●○○○ 20 ptsGiven that the terminal side of angle $\theta$ passes through $(-2, 3)$, find the value of $\cos\left(\theta + \frac{3\pi}{2}\right)$. Round to two decimal places.
3. Trig expression from a point on the terminal side ●●●○○ 50 ptsLet $\alpha$ be an angle in the second quadrant. The point $P(x, \sqrt{5})$ lies on the terminal side of $\alpha$, and $\cos\alpha = \frac{\sqrt{2}}{4}x$. Find $4\cos\left(\alpha + \frac{\pi}{2}\right) - 3\tan\alpha$. Round to two decimal places.