f = 2xy in the x dir, (x^2 - z^2) in the y dir, -3xz^2 in the z dir.(adsbygoogle = window.adsbygoogle || []).push({});

particle travles from (0,0,0) to (2,1,3)

im supposed to find the line integral from (0,0,0) to (2,1,3).

if i make z = 3/2 x and y = 1/2 x and substitute those into the integral of F dot dl i end up with an answer of -27.66667. the way im doing it makes sense from the things ive seen on the net. but the book gives an answer of -39.5. ??

also, ive got another problem, my electro-magnetics prof didnt get a chance to do any examples on this stuff. D = 2 Ro z^2 in the Ro dir, and Ro cos^2 theta in the z dir.

find closed surface integral of D dot Ds.

0<Ro<5

-1<z<1

0<theta<2pi

ive got no idea on this one. is it basically the same thing as a line integral or do i do something different?

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# Need help with some vector calculus problems

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