Is cos(-1/(sqrt(2)))=cos((sqrt(2))/2) ?

The answer to whether cos(-1/(sqrt(2)))=cos((sqrt(2))/2) is True

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

prove cos(-1/(sqrt(2)))=cos((sqrt(2))/2)

prove

cos (- \frac{1}{2}) = cos (\frac{2}{2})

True

Solution steps

cos (- \frac{1}{2}) = cos (\frac{2}{2})

Manipulating left side

cos (- \frac{1}{2})

Use the negative angle identity:

cos (- x) = cos (x)

= cos (\frac{1}{2})

Simplify

= cos (\frac{2}{2})

We showed that the two sides could take the same form

\Rightarrow True

(\frac{1}{2} sin^{2} (θ)) = (\frac{1}{2} cos (2 θ))

(sin (3 x) + cos (3 x))^{2} = 1 + sin (6 x)

sin (x - π) = sin (x) - sin (π)

cos (- \frac{2}{3} π) = cos (\frac{4 π}{3})

- cos^{2} (x) = \frac{1 - csc ^{2} ( x )}{cos ^{2} ( x )}

Is cos(-1/(sqrt(2)))=cos((sqrt(2))/2) ?
The answer to whether cos(-1/(sqrt(2)))=cos((sqrt(2))/2) is True