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Expert: - 4/29/2008


Question
A particle that moves along a straight line has velocity
v(t)=t^(2)*e^(-3t)
meters per second after t seconds. How many meters will it travel during the first t seconds?

I did integration by parts twice for this problem. and then upper minus lower ( t - 0 ). but for some reason it was wrong.  I would appreciate you help! Thank you!!

Answer
My answer is -( 1/3 ) * ( t^2 + (2/3)t + 2/9 ) * ( e^(-3t) ) + 1/3

I don't know if this is correct as I did it in a rush...

If my answer coincides with yours, maybe the expected one is wrong,which  may be very probable.

At least, using integration by parts twice is absolutely correct, as the
index for t is 2 before e^(-3t)

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