Parabolic Cylinder line integral

christopnz
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1.Homework Statement

(Parabolic Cylinder) find the area of the surface extending upward form x^2 + y^2 =1 to z = 1 - x^2 using line integral

2.

Could some one please outline the method to solving this. I tryed using spherical corridinates but am unsure if this was correcect

The Attempt at a Solution

 
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Surely, since this is a cylinder, cylindrical coordinates would be better? That is, use polar coordinates for two coordinates, z for the third. x= r cos(\theta), y= r sin(\theta) so you will be integrating z= 1- x^2= 1- r^2 cos^2(\theta) over the unit circle.
 
ty that helped alot
 
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