Question

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

Answer 1

This is simply the graph of `sin(x)` with the amplitude stretched to `[-3,+3]`

Explanation:

`sin(x)+2sin(x)= 3 sin(x)`
`sin(0)=0 rArr 3 sin(0)=0`
`sin(pi/2)=1 rArr 3 sin(pi/2)=3`
etc.
graph{3sin(x) [-5.986, 6.504, -3.1, 3.144]}