# Calculus

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Use integration by parts to find the given integral:

∫_9^1 (7t - 42)e^(7 - t)

= [-28(1 + e^8)] / e^2

Is my answer correct?

or... is it..

= -70e^(-2) + 14e^6

• Calculus -

Is your 9^1 a misprint? What is the purpose of the 1? Why is there no "dt" in your integral?

Both of your answers are incorrect, since they are constants. The indefinite integral would be a function of t, and the definite integral would have to have specified limits of integration. You did not mention any.

• Calculus -

it's 1^9 and I forgot to include dt... and I need to evaluate it when f(9) - f(1) and that's what my answer represents..

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