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    Hello,

    Can someone help with this integral? Preferably with steps:

    integral x^n exp(-x) dx

    Between 0 and infinity.
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    What have you tried?
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    (Original post by qrty12)
    Hello,

    Can someone help with this integral? Preferably with steps:

    integral x^n exp(-x) dx

    Between 0 and infinity.
    \displaystyle \int^{\infty}_0 x^ne^{-x} .dx ?

    Are you deriving a reduction formula or finding a limit, or what? Let's see what you've tried.
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    You can find a very simple expression for this integral.First though find a reduction formula. Are you assuming n is a positive integer?
    Spoiler:
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     \displaystyle \int_0^{\infty } x^ne^{-x} \ dx = \Gamma (n+1) .
 
 
 
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