You need to consider the following formula that helps you to find the amplitude, period and phase shift of the sine function, such that:
`y = Asin(Bx - C) + D`
`A ` represents the amplitude
`T =` `(2pi)/B` represents the equation of period
`C/B ` represents the phase shift
Comparing the equation of the given function `y = 2sin(30x - 90^o)` to the standard equation, yields that `A = 2, B = 30, C = 90^o` .
Since `A` represents the amplitude, yields that `A = 2` .
You may evaluate the period using the equation `(2pi)/B` such that:
`T = (2pi)/B => T = (2pi)/30 => T = pi/15`
You may evaluate the the phase shift using the equation `C/B` , such that:
phase shift `= C/B = 90^o/30 = 3`
Hence, evaluating the amplitude, period and phase shift, yields `A = 2, T = pi/15, C/B = 3.`