Is cos(2θ)= 1/(sec(2θ)) ?

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

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

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

p ro v e (cos (3 x) - cos (x)) = - 2 sin (2 x) sin (x)

p ro v e sec (\frac{π}{2} - y) = csc (y)

p ro v e cos (2 x - \frac{π}{2}) = cos (\frac{π}{2} - 2 x)

p ro v e sin (\frac{π}{2} - x) cot (\frac{π}{2} + x) = - sin (x)

p ro v e cos (x) \cdot csc (x) \cdot tan (x) = 1