Question

Find all solutions to the equation in the interval [0, 2pi). COS X = sin 2x​

Answer 1

Answer:

Step-by-step explanation:

cos x=sin 2x

sin 2x-cos x=0

2 sin x cos x-cos x=0

cos x(2 sin x-1)=0

either cos x=0

$x=\frac{\pi }{2},\frac{3\pi }{2}$

or

2 sin x-1=0

$sin x=\frac{1}{2} =sin (\frac{\pi }{6}),sin(\pi -\frac{\pi }{6} )\\x=\frac{\pi }{6} ,\frac{5 \pi }{6}$