Is cos(2*30)=cos^2(30)-sin^2(30) ?

The answer to whether cos(2*30)=cos^2(30)-sin^2(30) is True

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prove cos(2*30)=cos^2(30)-sin^2(30)

prove

cos (2 \cdot 30) = cos^{2} (30) - sin^{2} (30)

True

Solution steps

cos (2 \cdot 30) = cos^{2} (30) - sin^{2} (30)

Use the Double Angle identity:

cos (2 x) = cos^{2} (x) - sin^{2} (x)

\Rightarrow True

1 + tan^{2} (4 5^{\circ}) = sec^{2} (4 5^{\circ})

\frac{cot ( x )}{cos ( x )} = csc (x)

\frac{sin ( x ) cos ( x )}{tan ( x )} = cos^{2} (x)

2 sin^{2} (2 t) + cos (4 t) = 1

\frac{cos ( θ ) + cos ( 3 θ )}{2 cos ( 2 θ )} = cos (θ)

Is cos(2*30)=cos^2(30)-sin^2(30) ?
The answer to whether cos(2*30)=cos^2(30)-sin^2(30) is True