Question

2cos2theta=1+sintheta​

Answer 1

Answer:

1+sinx = 2cos^2x

1+sinx = 2(1-sin^2x

1+sinx = 2-2sin^2x

2sin^2x+sinx-1=0

(2sinx-1)(sinx+1)

2sinx-1=0

sinx=1/2

x=π/6, 5π/6 (in quadrants I and II where sin>0)