How do you solve for x in $sin(x) = sin(2x)$ where x is between [0,360]?

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Answer 1 · 2015-02-15T01:25:37

$x epsilon {0^o, 60^o, 180^o, 330^o}$

$sin(x) = sin(2x)$
By double angle formula:
$sin(x) = 2 * sin(x) * cos(x)$
$sin(x) = 0$ or $1 = 2 * cos(x)$

If $sin(x) = 0$
then $x = 0^O or 180^o$

If $1 = 2 * cos(x)$
then $cos(x) = 1/2$
$rarr$ $x = 60^o or 330^O$

How do you solve for x in sin(x) = sin(2x)sin(x) = sin(2x) where x is between [0,360]?