Use sumtoproduct formulas to find the solutions of the equat
Use sum-to-product formulas to find the solutions of the equation. (Use n as your arbitrary integer. Enter your answers as a comma-separated list.)
sin 5x ? sin x = 2 cos 3x
I understand how to get pin/3 + pi/6 but I don\'t understand how to get the other.
Solution
sin 5x sin x = 2 cos 3x
LHS : 2cos(3x)sin2x
2cos(3x)sin2x - 2 cos 3x =0
2cos3x( sin2x -1) =0
cos3x =0
3x = pi/2 + 2n*pi ; x= (pi + 4pi*n)/6
3x= 3pi/2 +2n*pi ; x= ( 3pi +3n*pi)/6
sin2x =1 ; 2x = pi/2 + 2n*pi
x = (pi + 4n*pi)/4
