Integration when given the exact value of an un-integratable function

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nick.martinez
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given that ∫ e^(-x^2) dx=√∏, calculate the exact value of ∫ e^-((x-a)^2)/c dx

limits of integration for both are from negative infinity to infinity.

I don't even know where to start on this one. I know how to integrate regular functions. How can I find the exact value for an integral I can't even integrate?

Please Help
 
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nick.martinez said:
given that ∫ e^(-x^2) dx=√∏, calculate the exact value of ∫ e^-((x-a)^2)/c dx

limits of integration for both are from negative infinity to infinity.

I don't even know where to start on this one. I know how to integrate regular functions. How can I find the exact value for an integral I can't even integrate?

Please Help

The trick in these problems is to turn the new integral into the known one by a substitution.

Can you think of a sub to turn that integral into [itex]\displaystyle \int_{-\infty}^{\infty} e^{-y^2}dy[/itex]?

I'm using y to avoid confusion here. Keep in mind that in a definite integral, the actual variable of integration doesn't matter (it's a dummy).