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hantu_ah

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math~ solve

who can solve this prob


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who can solve this prob


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well not that this belongs in 2 unit- or 4 unit for that matter, i believe all you have to do is integrate each expression singularly then multiply them together. so intergrating w.r.t y you get:
[e^y] 0>1 = (e-1)

integrating w.r.t x:
[-e^-x] 0>x^3 = (1- e^-x^3)
so all together you get:
(e-1)(1-e^x^3)
then just expand and simplify.

Not too sure though, i haven't done double integrals yet, hopefully ythis year =]
 

hantu_ah

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i think this is right

after i refer the real answer from my book, the answer is only 1/2.. :confused:


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marmsie

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I think the book might be wrong.

When I worked it out, I got the same answer and when I plugged the question into wolframalpha.com, it also gave the same result.

The input I used in wolframalpha was:
integrate integrate exp(y/x) dy from y = 0 to y=x^3 dx from x = 0 to x = 1
 

shaon0

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I think the book might be wrong.

When I worked it out, I got the same answer and when I plugged the question into wolframalpha.com, it also gave the same result.

The input I used in wolframalpha was:
integrate integrate exp(y/x) dy from y = 0 to y=x^3 dx from x = 0 to x = 1
Yeah you're right. Books wrong
 

jet

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Just moved to extracurricular :)
 

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