{xsin5xdx ..solve the intergratio

Question

amistre64 · Answer

your missing a -5; so id take one form -5/-5

jamesj · Answer

Use integration by parts.  Let u = x and v' = sin(5x).

Can you see what to do now?

amistre64 · Answer

.... i dint think it was out of order lol

amistre64 · Answer

sin(5x) comes from at least cos(5x)

Dx (cos(5x)) = -5 sin(5x) ... ack, im missing an x from that .  DOH!!

amistre64 · Answer

good thing i think it through ... bad thing i think it through afterwards ;)

gina · Answer

@ james can u try to continue after that kuz  ima finding it hard

jamesj · Answer

$$\int\limits u v' = u v - \int\limits u'v$$

There must be an example in your notes or your text book of using this rule.  Have a look at that example, line by line and then see how to apply it here.  I've given you already what the u and v would be.

jamesj · Answer

For example, http://www.math.ucdavis.edu/~kouba/CalcTwoDIRECTORY/intbypartssoldirectory/IntByPartsSol.html#SOLUTION 2

anonymous · Answer

http://www.wolframalpha.com/input/?i=integrate+x+Sin%5B5x%5D

gina · Answer

@ james thanx so much ,cud also help me some examples on double intergrations??

gina · Answer

@ robtobey nice answer too but some steps are missing