# Huh? Would you guys please look at this again...

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Posted by Joel on October 15, 2002 at 18:29:24:

In Reply to: Re: Correct! posted by T.Gracken on October 07, 2002 at 11:54:21:

: : The definite integral from 0 to 7 should be approx. 505.992? That's what i got but the answer key says its wrong?????????

: if yes, then did you round/approximate prior to finishing? (as that can create significant error)

: I calculated the definite integral (using your boundaries and result below) to 495.18

: If that is not what the answer key has, let us know and I (or someone else will recheck the work).

:
: : : : Integral of [e^x sinx] =

: : : : sin x e^x - cos x e^x - integral [ e^x sin x ]

: : : : =[(sin x)(e^x)-(cos x)(e^x)]/2 + C

I just noticed that there were more comments on this thread. I don't understand how either of you got those values. I'm getting a definite integral from 0 to 7 RADIANS as -52.64046.
Look: e^7 is approx. 1096.6
sin 0 is 0
cos 0 is 1
e^0 is 1
((.657-.754)*1096.6 - (-1))/2 = -52.68
(Or am I messing it up someplace?)
What DOES the answer key say?

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