Thread: graph of equation over given interval

Identify the graph of the equation over the given interval.

y=3sin (2x-pi/2)

x is greater than or equal to -pi/4 and x is less than or equal to 3pi/2.

I think I found the period to be: pi
the amplitude is 3.
the phase shift is pi as well?

I'm unsure as to what to do after this though.

My choices are these, but I don't know how to determine which is correct. I'm not just looking for an easy answer, I really want to try to understand this. Thanks so much guys.

Actually, phase shift is since:

Now from your typical graph, make the changes accordingly. Change its amplitude to 3. Shift it to the right units. Adjust the period.
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Alternatively ...

To make things easier, note that:

So we have:

Much easier to graph