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supercali
Aug21-08, 01:31 PM
1. The problem statement, all variables and given/known data
let F be vector field:
\[\vec F = \cos (xyz)\hat j + (\cos (xyz) - 2x)\hat k\]
let L be the the curve that intersects between the cylinder \[(x - 1)^2 + (y - 2)^2 = 4
\] and the plane y+z=3/2
calculate:
\[\left| {\int {\vec Fd\vec r} } \right|\]

2. Relevant equations
in order to solve this i thought of using the stokes theorem because the normal to the plane is \[\frac{1}{{\sqrt 2 }}(0,1,1)\]
thus giving me
\oint{Fdr}=\int\int{curl(F)*n*ds}=\int\int{2/sqrt{2}*\sin(xyz)}


i tried to parametries x y and z x= rcos(t)+1 y=rsin(t)+2 z=1/2-rsin(t)

but it wont work

NoMoreExams
Aug21-08, 01:43 PM
Would x = 1 + 2 cos(t), y = 2 + 2 sin(t) and z = -1/2 - 2 sin(t) do the trick?

supercali
Aug21-08, 01:54 PM
i wonder if it is allowed given we have to do a multiple integral needing 2 variables

NoMoreExams
Aug21-08, 02:15 PM
Why wouldn't you just use Green's?

supercali
Aug21-08, 03:09 PM
using green or stokes is the same thing green is just a private solution of stokes and if you use it you are still stuck with that sin(xyz)

NoMoreExams
Aug21-08, 03:30 PM
See what Halls answered you in the other thread.