If I had an integral(adsbygoogle = window.adsbygoogle || []).push({});

[tex] \int_{-1}^{1}e^{x}dx [/tex]

Then performing the substitution [itex] x=\frac{1}{t} [/itex] would give me

[tex] \int_{-1}^{1}-e^\frac{1}{t}t^{-2}dt [/tex]

Which can't be right because the number in the integral is always negative. Is this substitution not correct?

Sorry if I am being very thick but I can't figure out why I can't evaluate this simple integral with this change of variables.

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# Gaussian Integral Substitution

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