How do you prove: $2 sin x = cos x$ $2sinx = cosx$ ?

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How do you prove: $2 sin x = cos x$ $2sinx = cosx$ ?

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Answer 1 · 2018-03-09T14:33:03

This can not be proven since it is not (in general) true.

Explanation:

As an obvious counter example:
If $x = 0$ $x=0$
then $sin (x) = 0$ $sin(x)=0$ and $cos (x) = 1$ $cos(x)=1$
and obviously $2 \cdot sin (x) \neq cos (x)$ $2 * sin(x) != cos(x)$

Perhaps (?) you wanted to solve for $x$ $x$ given this equation.

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How do you prove: $2 sin x = cos x$ $2sinx = cosx$ ?

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