How do you integrate # (x^(7))e^(x^(8)) dx#?

2 Answers
Apr 17, 2015

#int x^7e^(x^8) dx#

Use substitution to write this an an integral of #e^u du#

Let #u = x^8#. This makes #du = 8x^7 dx#,

#int x^7e^(x^8) dx = 1/8 int e^(x^8)(8x^7) dx = 1/8 int e^u du#

#=1/8 e^u +C = 1/8 e^(x^8) +C#

(Check by differentiating #1/8 e^(x^8) +C#)

Apr 17, 2015

STEP 1:

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STEP 2:

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