Question

How do you determine the amplitude of `y= -2 sin x`?

Answer 1

Every time you have a trigonometric function have a look at the number that is multiplying it, basically the number "in front" of it:
In this case you have:
`y=-2*sin(x)` the number is `-2`. That represents your AMPLITUDE !!!!
So this function is oscillating between `+2` and `-2`.

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