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nubeer
find the area of the surface generated by revolving r^2=cos2x about y axis. this question is related to polar coordinates.
|dw:1324838256977:dw| The function resembles two leaves defined between -pi/4 to pi/4, and from 3pi/4 to 5pi/4. Outside of these limits, r is not defined in real. Is this what you expect?
Question: is the "x" in r^2=cos2x meant to be theta, or is this x equals rcos(theta)?
yes was theta i just changed in x