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zzheng
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Sorry I am new to the forum, I don't know how to type in the integrals and stuff.
Let S be the portion of the surface y = x2 where 0 <= z <= X <= 2. Compute the surface area of S.
r(u,v) = x(u,v)i + y(u,v)j + z(u,v)k
A(S) = integral ru X rv dA
My first attempt I did: x = ucosv, y = u2cos2v, and z = ucosv where 0<= u <= 2 and 0 <= v <= 2pi
when I was doing ru X rv, got a lot of sines and cosines but everything canceled out at the end and became 0.
Then I just decided to use x = x, and y = x2 where x is from 0 to 2.
but then ry turns out to be 0.
I am not sure how I would do this, most of the problems I have done are z as a function of x and y, but this case z is given but I don't know what to do with it.
Could some one please help me with this? Thank you for your help in advance.
Homework Statement
Let S be the portion of the surface y = x2 where 0 <= z <= X <= 2. Compute the surface area of S.
Homework Equations
r(u,v) = x(u,v)i + y(u,v)j + z(u,v)k
A(S) = integral ru X rv dA
The Attempt at a Solution
My first attempt I did: x = ucosv, y = u2cos2v, and z = ucosv where 0<= u <= 2 and 0 <= v <= 2pi
when I was doing ru X rv, got a lot of sines and cosines but everything canceled out at the end and became 0.
Then I just decided to use x = x, and y = x2 where x is from 0 to 2.
but then ry turns out to be 0.
I am not sure how I would do this, most of the problems I have done are z as a function of x and y, but this case z is given but I don't know what to do with it.
Could some one please help me with this? Thank you for your help in advance.