You left it a bit late didn't you? Anyway, please provide your thoughts on a solution to the problem (for example, do you know any methods of integrating products?) Better still, in future, use the homework posting template with which you were provided!
Well since you dont really have much time, Ill just get through to you the essentials, But can't give you the answer.
[tex]\int u dv= uv-\int v du[/tex]
Let u=x, dv= e^(1-x) dx. Differentiate u with respect to x, and take the dx to the other side to get du. Integrate dv to get v. Once you have those values, sub them into that equation and your done. Good Luck
EDIT: O btw this is obviously calculus, put this is the calculus section next time.
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