Question

Find the exact value sin(7pi/4)

Answer 1

We know that the reference angle for $\frac{7\pi}{4}$ in standard position is $\frac{\pi}{4}$. Since the sine function is negative in the third and fourth quadrants, the exact value of $\sin\left(\frac{7\pi}{4}\right)$ is $\boxed{-\frac{\sqrt{2}}{2}}$.