Is (1-tan^2(x))(1+tan^2(x))=cos(2x) ?

The answer to whether (1-tan^2(x))(1+tan^2(x))=cos(2x) is False

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prove (1-tan^2(x))(1+tan^2(x))=cos(2x)

prove

(1 - tan^{2} (x)) (1 + tan^{2} (x)) = cos (2 x)

False

Solution steps

(1 - tan^{2} (x)) (1 + tan^{2} (x)) = cos (2 x)

Show that the two sides are not equal

\Rightarrow False

sin (0) sec (0) = tan (0)

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

cos (2 a) = \frac{cot ( a ) - tan ( a )}{csc ( a ) sec ( a )}

\frac{1}{sin ( θ )} = sin (θ) + cos (θ) cot (θ)

cos (a) cos (b) = \frac{1}{2} (cos (a - b) + cos (a + b))

Is (1-tan^2(x))(1+tan^2(x))=cos(2x) ?
The answer to whether (1-tan^2(x))(1+tan^2(x))=cos(2x) is False