Recent content by ShaneOH

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    Double Integration using u-substitution

    Hey guys, I'm sorry to bring the same problem up again, but my answer is lacking two entire terms and I'm not sure what I'm omitting. Problem: ∬ √(x + 4y) dxdy, where R = [0, 1] x [2, 3] Solution attempt: I would assume that, u = x + 4y du = 1 dx (since we're integrating with respect to x...
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    Double Integration using u-substitution

    So they become variable bounds. Got it. Thanks so much for the help and patience Sourabh!
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    Double Integration using u-substitution

    So (last question!) what you're saying is, if this problem would have been such that u = 2x + 4y, then the bounds would have been from 4 to 6? I literally just completely drop the y? Ignore it? Say, u = 2x + xy + y, and normal bounds are from 2 to 4 Then, change of bounds: u = 2(2) + 2...
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    Double Integration using u-substitution

    Sure, so I'm confused on: Single variable substitution: Let's say you have some arbitrary integration problem from 2 to 4, of √(x^2 + x). Here, u = x^2 + x du = 2x + 1 dx dx = du/2x + 1 And so, instead of 2 to 4, the bounds become: (2)^2 + (2) = 6 (4)^2 + 4 = 20 So the...
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    Double Integration using u-substitution

    @Sourabh. Sure thing, it just looked... wrong, but I'll take a crack at continuing. @daveb: I was under the impression I needed u-substitution for more than one value under a square root? Or does it just become (2(x+C)^(3/2))/3)? Also: Could someone just shed some light on my change of...
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    Double Integration using u-substitution

    Homework Statement Hey guys, so we're going over multiple integration in Calc III, and I'm having trouble with the more complex problems. ∬ √(x + 4y) dxdy, where R = [0, 1] x [2, 3] So it's 0 to 1 on the outside integral, 2 to 3 on the inside integral, of sqrt(x+4y) dxdy. Homework...
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