Is cos^2(B)= 1/2 (1+cos(2B)) ?

The answer to whether cos^2(B)= 1/2 (1+cos(2B)) is True

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prove cos^2(B)= 1/2 (1+cos(2B))

prove

cos^{2} (B) = \frac{1}{2} (1 + cos (2 B))

True

Solution steps

cos^{2} (B) = \frac{1}{2} (1 + cos (2 B))

Manipulating right side

\frac{1}{2} (1 + cos (2 B))

Rewrite using trig identities

= cos^{2} (B)

We showed that the two sides could take the same form

\Rightarrow True

sin (θ + π) = - sin (θ)

tan^{2} (x) sec^{2} (x) - tan^{2} (x) = tan^{4} (x)

sin^{2} (x) + 3 cos^{2} (x) = 1 + 2 cos^{2} (x)

sec (2 θ) = \frac{csc ^{2} ( θ )}{csc ^{2} ( θ ) - 2}

sin (x + \frac{3 π}{2}) = - cos (x)

Is cos^2(B)= 1/2 (1+cos(2B)) ?
The answer to whether cos^2(B)= 1/2 (1+cos(2B)) is True