solve 3sin(pi/4*x)=2 for the four smallest positive solutions

Answer 1

3sin(pi/4*x)=2
sin(pi/4*x)=2/3
I am using radians, since you are using π in your angles.
π/4 x = .7297 or pi/4*x = 2.411895 because the sine is positive in quads I and II
x = .9291 or x = 3.07088

the period sin π/4*x is 2π/(π/4) = 8

so adding 8 to any existing angle will yield another answer.
so other solutions are:

So the 4 smallest positive solutions are:
x = .9291, 3.07088, 8..9291 and 10.07088