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

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

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

prove

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

False

Solution steps

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

Show that the two sides are not equal

For

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

plug in

x = 1

sin^{2} (1) = 0.70807 \dots

sin^{2} (1)

Refine to a decimal form

= 0.70807 \dots

1 - cos (2 \cdot 1) = 1.41614 \dots

1 - cos (2 \cdot 1)

Refine to a decimal form

= 1.41614 \dots

The two sides are not equal

\Rightarrow False

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

sin (4 a) = 2 sin (2 a) cos (2 a)

tan (x) = sec (x) sin (x)

sin (2 D) = 2 cot (D) sin^{2} (D)

tan^{2} (\frac{π}{6}) = \frac{1}{3}