# How do you graph sin x + 2 sin x?

This is simply the graph of $\sin \left(x\right)$ with the amplitude stretched to $\left[- 3 , + 3\right]$
$\sin \left(x\right) + 2 \sin \left(x\right) = 3 \sin \left(x\right)$
$\sin \left(0\right) = 0 \Rightarrow 3 \sin \left(0\right) = 0$
$\sin \left(\frac{\pi}{2}\right) = 1 \Rightarrow 3 \sin \left(\frac{\pi}{2}\right) = 3$