Question

Find the amplitude of the function.
y=-3sinx

Answer 1

A general form of sine wave is :
y = A sin (wx + b)

where |A| is the amplitude.

for example,
if we had
y = -10 sin (2x+3)

the amplitude will be
A = |-10| = 10

got this?

Answer 2

so can you now figure out the amplitude of
y=-3sinx
?