Consider porperties of y=sin(x) (x in radians)

maximum values (amplitude): 1, -1
0 values (crosses x axis): 0, pi, 2pi, 3pi,... (period=2pi)

Pick a starting point (0,0) and plot the series:

x y
0 0
0 1
pi 1
pi -1
2pi -1
2pi 1
. .
. .
. .

From there it's not too difficult to relate x and y to the generic
y=Asin(Bx) where A=amplitude (y=A or -A) and 2pi*B=period
(x=i*period/2)


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MrShorty
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