Question

Evaluate given trigonometry equation 2sin² 0 (theta)- cos 0(theta)= 1​

Answer 1

Answer:

sorry i didn't understand

Step-by-step explanation:

sorry

Answer 2

Answer:

Step-by-step explanation:

2sin^2 theta - cos theta = 1

2 sin^2 theta = cos theta + 1

2 [ 1 - cos^2 theta] = 1+ cos theta.                   ( here sin^2theta =1-cos^2 theta)

2 [ (1+ cos theta) ( 1 - cos theta)] = 1 + cos theta  ( we know a^2-b^2=(a+b)(a-b))

2(1 +cos theta ) = 1

2 + 2 cos theta = 1

2cos theta = 1 -2

cos theta = -1/2

so , theta = 120 degree