Question

Find all solutions to the equation in the interval [0, 2π)

2 cos x + sin 2x = 0

Answer 1

hi kcb,, the trig identity is: sin 2x=2sin x cos x

Answer 2

therefore, 2cos x +2sin x cos x+0

Answer 3

im sorry,its equal to zero 2cos x +2sin x cos x=0

Answer 4

now take out the cos x,... cos x (2+2sin x)=0

Answer 5

here both are equaled to zero that is,
cos x =0 and 2+2 sin x = 0

Answer 6

x=arc cos 0 and 2sin x=-2
sin x=-2/2
sin x=-1
x=arc sin -1
x=pi/2 and x=-pi/2