Is sin(x)sin(3x)=4sin(x)cos^2(x) ?

The answer to whether sin(x)sin(3x)=4sin(x)cos^2(x) is False

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prove sin(x)sin(3x)=4sin(x)cos^2(x)

prove

sin (x) sin (3 x) = 4 sin (x) cos^{2} (x)

False

Solution steps

sin (x) sin (3 x) = 4 sin (x) cos^{2} (x)

Show that the two sides are not equal

For

sin (x) sin (3 x) = 4 sin (x) cos^{2} (x)

plug in

x = 1

sin (1) sin (3 \cdot 1) = 0.11874 \dots

sin (1) sin (3 \cdot 1)

Refine to a decimal form

= 0.11874 \dots

4 sin (1) cos^{2} (1) = 0.98259 \dots

4 sin (1) cos^{2} (1)

Refine to a decimal form

= 0.98259 \dots

The two sides are not equal

\Rightarrow False

sec (\frac{π}{2} - t) = csc (t)

- sin (2 θ) = \frac{- 2 cot ( θ )}{1 + cot ^{2} ( θ )}

csc (x) sec (x) = tan (x) + cot (x)

cot^{2} (\frac{x}{2}) = \frac{sec ( x ) + 1}{sec ( x ) - 1}

sin (3 u) = sin (u) (3 - 4 sin^{2} (u))

Is sin(x)sin(3x)=4sin(x)cos^2(x) ?
The answer to whether sin(x)sin(3x)=4sin(x)cos^2(x) is False