4sin^2 3x-sin3x=2+sin^2 3x

4sin²3x-sin3x=2+sin²3x

3sin²3x-sin3x-2=0

z=sin3x

3z²-z-2=0 D=1+24 √D=√25=5 z1=1/6[1+5]=1 z2=1/6[1-5]=-4/6=-2/3

sin3x=1 3x=π/2+2πn x=π/6+2/3*πn n∈Z

sin3x=-2/3 3x = (-1) ⁿarcsin (-2/3) + πn x = (-1) ⁿ*1/3*arcsin (-2/3) + πn/3π n∈Z