Hi, I'm just going through a practice exam and looking over my answers compared to the answer key.

$\displaystyle y=3sin(x+\frac{\pi}{3}) - 1$

It asked for therange of the function in interval notation.

I put down [-1, 2], because I figured the amplitude was 3?

But the answer is[-4, 2]

I need some clarification as to why. Am I missing something? Do I multiply the amplitude by 2 or something weird?

Thanks in advanced.