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Homework Statement
This isn't for homework but the question fits the general HW format. Basically, I am getting a different answer from my colleague on the double integral below so I am trying to find out why. I am trying to put this into excel so I can play with the numbers and see the different results. The double integral is attached (Image upload wasn't working, hopefully this isn't a big deal).
Homework Equations
The values I am using are as follows:
a: 2
b:1.2
c:1
The Attempt at a Solution
So the first integration (with respect to y) yields me this:
(.5)*(((x^2)*(arsinh((sqrt((a^2)(x^2)))/x)))(b*(sqrt((x^2)+(b^2))))+(a*(sqrt((a^2)(x^2))))((x^2)*(arsinh(b/x))))
Remember, I am putting this through excel so I am keeping the variables in there until the end. The second integration (with respect to x now) yields me this:
.5*(((b^3)*(arsinh(c/b)))+((a^3)*(arcsin(c/a)))((b*c)*(sqrt((c^2)+(b^2))))+((a*c)*(sqrt((a^2)(c^2)))))
So now that I have this, I can have excel plug in the variables listed in the above section and get the answer. With the variables above, I am getting ~2.234. My colleague, however, is getting ~2.361. I do not have access to his work, and he seems confident in his answer. Basically I am bringing up this issue a couple years after he did the original problems and he isn't allotted any more time to work on this so I'm on my own. Is there something I am doing wrong?
Thanks
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