Question

Sin^2 3x + sinx+cos^2 3x=0

Answer 1

sin²3x+sinx+cos²3x=0
(sin²3x+cos²3x)+sinx=0
1+sinx=0
sinx=-1
x=3π/2+2πn, n∈Z

Answer 2

(sin²3x+cos²3x) +sinx=0
sinx=-1
x=-π/2+2πn, n € Z