# How do you solve Sin(x + pi/4) + Sin(x - pi/4) = -1?

Solutions in [0, 2$\pi$] are 5$\pi$/4 and 7$\pi$/4.
Use sin (A+B) + sin(A$-$B) = 2 sin 2A sin 2B.
The equation reduces to sin x = $-$1/sqrt2.