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blackdarkeye
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Homework Statement
Integrate the function f(x,y,z)=−4x+3y over the solid given by the figure below, if P = (5,1,0) and Q = (-5,1,2).
[PLAIN]http://img259.imageshack.us/img259/958/sfig1681g1.gif
Homework Equations
x=rcos([tex]\theta[/tex])
y=rsin([tex]\theta[/tex])
r=sqrt(x^2+y^2)
The Attempt at a Solution
i converted it into cylindracl coordinates and got
[tex]\int[/tex][tex]\int[/tex][tex]\int[/tex] -4rcos([tex]\theta[/tex])+3rsin([tex]\theta[/tex]) r dzdrd[tex]\theta[/tex]
limits were arctan(-1/5)<[tex]\theta[/tex]<arctan(1/5), 0<z<2, 0<r<[tex]\sqrt{26}[/tex]
after integrating i got
-(8/3)(26^(3/2))sin(atan(1/5))-(2)(26^(3/2))cos(atan(1/5))+(8/3)(26^(3/2))sin(atan(-1/5))+(2)(26^(3/2))cos(atan(-1/5))
but apparently that is wrong. I need help!
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