Is cos^2(A)-sin^2(A)=2cos^2(A)-1 ?

The answer to whether cos^2(A)-sin^2(A)=2cos^2(A)-1 is True

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

prove cos^2(A)-sin^2(A)=2cos^2(A)-1

prove

cos^{2} (A) - sin^{2} (A) = 2 cos^{2} (A) - 1

True

Solution steps

cos^{2} (A) - sin^{2} (A) = 2 cos^{2} (A) - 1

Manipulating left side

cos^{2} (A) - sin^{2} (A)

Rewrite using trig identities

= 2 cos^{2} (A) - 1

We showed that the two sides could take the same form

\Rightarrow True

\frac{1}{sec ( x )} = sec (x) - tan (x) sin (x)

sin (a + b) sin (a - b) = sin^{2} (b) - sin^{2} (a)

\frac{tan ( x ) + cot ( x )}{tan ( x )} = csc^{2} (x)

tan (x - \frac{π}{4}) = \frac{tan ( x ) - 1}{tan ( x ) + 1}

1 - csc^{2} (x) tan^{2} (x) = - tan^{2} (x)

Is cos^2(A)-sin^2(A)=2cos^2(A)-1 ?
The answer to whether cos^2(A)-sin^2(A)=2cos^2(A)-1 is True