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# Trig question watch

1. Ok so the first part of the question was express 3Sin x - 4Cosx in the form

R Sin (x-a)

I got this as 5 Sin (x - 53.1)

The next part is, find the smallest positive value of X in degrees for which the expression takes its greatest value? I dont get what it means any hep?
2. (Original post by SunDun111)
Ok so the first part of the question was express 3Sin x - 4Cosx in the form

R Sin (x-a)

I got this as 5 Sin (x - 53.1)

The next part is, find the smallest positive value of X in degrees for which the expression takes its greatest value? I dont get what it means any hep?
Think about the graph of y = sin(x). For what positive values of x does y have it's maximum value?
3. Putting it in that form makes it easier to find the maximum value. You know that sin X (X is any angle) lies between -1 and 1 inclusive so the maximum of that function is...

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