Use '3 sin x - 4(sin x)^3' to show that if sin x = sin (3x), then sin x = 0 or.... 1. The problem statement, all variables and given/known data Use double-angle and addition formulæ and other relations for trigonometrical functions to find an expression for sin(3x) in terms of sin x alone. Use the expression you have found to show that, if sin x = sin (3x) , then either sin x = 0 or sin x = (+ or -)1/sqrt(2) 2. Relevant equations 3. The attempt at a solution I have found that [tex]sin(3x) = 3 sin x - 4 sin^3 x[/tex] (I think). However, I do not know what is meant by the latter part of the question. Would love for someone to explain it to me!