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Pyroadept
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Homework Statement
∫ e^([tex]\pi[/tex]x^2) dx, with limits -∞ to ∞
Homework Equations
∫∫ dxdy = ∫∫ rdrdθ
The Attempt at a Solution
Hi, here's what I've done so far:
Introduce a dummy variable y to get
∫∫ e^[tex]\pi[/tex](x^2 + y^2) dxdy, with limits -∞ to ∞ for both dx and dy
Introduce polar coordinates: x^2 + y^2 = r^2
The equation becomes:
∫∫ e^([tex]\pi[/tex]r^2) rdrdθ
But I don't know how to change the limits. Am I right in that the r limits stay the same and the θ limits change to [tex]\pi[/tex]/2 and -[tex]\pi[/tex]/2?
If this is right, when I integrate the first part, I end up with 0. Is this correct?
Thanks for any help.
P.S. I don't know why the pi is higher than the other figures, but it's meant to be at the same level!