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Hi
I need INTegral from 0 to ∞ of : x*e^(-x) dx
I use IBP: u = x, du = dx
dv = e^(-x) dx, v = -e^(-x)
uv - ∫v du = -x*e^(-x) - ∫ -e^(-x) dx
I am trying to evaluate the uv term : -x*e^(-x) from 0 to ∞
for the ∞ term of -x*e^(-x) =
-inf * 1/e^(inf) = -inf * 1/inf = 1
OR
-inf * 1/e^(inf) = -inf * 1/inf = -inf * 0 = 0
OR
it is indeterminate form, use l hospital...
which path is correct one ?
for the 0 term of -x*e^(-x) = 0
I am really sorry for the noob calculus question.
This is part of larger question regarding Gauss Quadrature. but..
Kindly pls remind me of the correct one.
Thank you for your help
I need INTegral from 0 to ∞ of : x*e^(-x) dx
I use IBP: u = x, du = dx
dv = e^(-x) dx, v = -e^(-x)
uv - ∫v du = -x*e^(-x) - ∫ -e^(-x) dx
I am trying to evaluate the uv term : -x*e^(-x) from 0 to ∞
for the ∞ term of -x*e^(-x) =
-inf * 1/e^(inf) = -inf * 1/inf = 1
OR
-inf * 1/e^(inf) = -inf * 1/inf = -inf * 0 = 0
OR
it is indeterminate form, use l hospital...
which path is correct one ?
for the 0 term of -x*e^(-x) = 0
I am really sorry for the noob calculus question.
This is part of larger question regarding Gauss Quadrature. but..
Kindly pls remind me of the correct one.
Thank you for your help