# Ratio Of Different Trigonometric Functions!

Geometry Level 3

If $\dfrac {\cos {3A}}{\cos {A}}$ $= \dfrac {1}{2}$, then the value of $\dfrac {\sin {3A}}{\sin {A}}$ can be expressed as $\dfrac {a}{b}$, where $a$ and $b$ are coprime positive integers, find $a+b$.

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