Integration 0 to infinity (x^4 e^-2ax dx)

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You should evaluate the improper integral such that:

`int_0^(oo)x^4*e^(-2ax) dx = lim_(n->oo) int_0^n x^4*e^(-2ax) dx`

You need to use integration by parts such that:

`int udv = uv - int vdu`

`u = x^4 => du = 4x^3dx`

`dv = e^(-2ax) dx => v = (e^(-2ax))/(-2a)`

`int x^4*e^(-2ax) dx = (x^4*e^(-2ax))/(-2a) + int 4x^3(e^(-2ax))/(2a) dx`

`int x^4*e^(-2ax) dx = (x^4*e^(-2ax))/(-2a)+ (2/a)int x^3(e^(-2ax)) dx`

You need to use integration by parts to evaluate `int x^3(e^(-2ax)) dx `  such that:

`u =x^3 => du = 3x^2 dx`

`dv = e^(-2ax) dx => v = (e^(-2ax))/(-2a)`

`int x^3(e^(-2ax)) dx = (x^3*e^(-2ax))/(-2a) + int 3x^2(e^(-2ax))/(2a) dx`

`int x^3(e^(-2ax)) dx = (x^3*e^(-2ax))/(-2a) + (3/2a) int x^2(e^(-2ax)) dx`

You need to use integration by parts to evaluate `int x^2(e^(-2ax)) dx`  such that:

`u = x^2 => du = 2x dx`

`dv =...

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