Is cos(2θ)= 1/(sec(2θ)) ?

The answer to whether cos(2θ)= 1/(sec(2θ)) is True

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prove cos(2θ)= 1/(sec(2θ))

prove

cos (2 θ) = \frac{1}{sec ( 2 θ )}

True

Solution steps

cos (2 θ) = \frac{1}{sec ( 2 θ )}

Use the basic trigonometric identity:

cos (x) = \frac{1}{sec ( x )}

\Rightarrow True

\frac{1}{csc ^{2} ( A )} + \frac{1}{cot ^{2} ( A )} = 1

(cos (3 x) - cos (x)) = - 2 sin (2 x) sin (x)

sec (\frac{π}{2} - y) = csc (y)

cos (2 x - \frac{π}{2}) = cos (\frac{π}{2} - 2 x)

sin (\frac{π}{2} - x) cot (\frac{π}{2} + x) = - sin (x)