Iterated Integral Homework: Evaluate I=∫01∫1+y1-y(6y2+10x)dxdy

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Homework Statement


Evaluate the iterated integral I = \int^{1}_{0}\int^{1+y}_{1-y} (6y^2+ 10x) dxdy

Homework Equations



. . . ?

The Attempt at a Solution


Integrate with respect to x gives me the following equation.
\int^{1}_{0} 6xy^2 + 5x^2 dy
I plug in y+1 and y-1 into x and get the following
6y2+12y3+6y4+5+10y+5y2-6y+12y3-6y4-5+10y-5y2
Most of the stuff cancels out giving me
12y3+12y3+10y+10y
which simplifies to
\int^{1}_{0} 24y^3+20y dy
and after integration I get
6y4+10y2
and after plugging in my numbers I get
6+10 = 16 which is wrong. I am not sure where I screwed up.
 
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I only briefly looked at your work, but you might want to check your substitution of limits in the first integrand.
 
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You, were right! I screwed up by substituting the limits into the y instead of x by mistake. Thanks a lot.
 
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