Wondered if anyone could advise

Plotting

y=sin(x)

gives a traditional sine curve with a positive lobe initially for values of x = 0 to 180 degrees, with a maximum of y=1 at 90 degrees. This is followed by a negative lobe for values x from 181 to 360 degrees, with a minimum of y=-1 at 270 degrees. Betwen these two lobes the plot crosses the y axis at x=180.

How would I go about “shifting” the centre of the plot to make the lobes asymmetrical? The maximum and minimum would remain the same, and the function should still “repeat” every 360 degrees, but the position that the plot crosses the X axis should be shifted from x=180 to (for example) x = 90.

Thus the target curve has a positive lobe for values of x from 0 to 90 degrees, but the a negative lobe for values of x from 91 to 360.

Currently I can get the first “compressed” part of the curve (ie a positive lobe that spans ninety degrees) by using

y=sin(2x).

Similarly I can get an “extended” curve where each lobe spans 270 degrees with

y=sin(2x/3)

But my attempts to either “flip” it from one equation to the other using if/then statements have failed to generate a singe equation that will provide the curve (this is the preferred option) have failed.

Can anyone help?