Is sin(a/2)= 1/2 sin(a) ?

The answer to whether sin(a/2)= 1/2 sin(a) is False

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prove sin(a/2)= 1/2 sin(a)

prove

sin (\frac{a}{2}) = \frac{1}{2} sin (a)

False

Solution steps

sin (\frac{a}{2}) = \frac{1}{2} sin (a)

Show that the two sides are not equal

For

sin (\frac{a}{2}) = \frac{1}{2} sin (a)

plug in

a = 1

sin (\frac{1}{2}) = 0.47942 \dots

sin (\frac{1}{2})

Refine to a decimal form

= 0.47942 \dots

\frac{1}{2} sin (1) = 0.42073 \dots

\frac{1}{2} sin (1)

Refine to a decimal form

= 0.42073 \dots

The two sides are not equal

\Rightarrow False

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