cos^2 x sin x -4 times sin x if 0 ° < x < 360 °

Question

i cannot figure out how to solve for x

Answer 1

cos^2x(sinx) -4sinx =0

(sinx)[cos^2x -4] =0 set each factor =0

sinx=0 cos^2x-4=0

cos^2x =2

cosx =+ or -2

sinx = 0 when x= 0 or pi

cosx = 2 or -2 is impossible. cosines are always less than 1 and greater than -1, -1<x<1

only solution is x =0 and x=pi = 180 degrees

but you have 0<x<360, so 0 can't be a solution

Only solution is x=pi or 180 degrees