Recent content by XedLos

I have a general question what are some techniques to identifying what type of integration you need to make when given an integral. How do you make the choice what to choos as u or v when doing integration by parts? What about trig integration. What are teh steps you take to solve the...

I hit the submit instead of the preview. please wait Homework Statement \int9s9^s dsHomework Equations ∫udv=uv-∫9^sds-∫vduThe Attempt at a Solution u=9s du=9ds dv=9^s ds v=∫9^sds =∫3^(2s) ds =3^(2s)/[2ln(3)] this is as far as i have gotten. Am i correct so far?

what do u mean how should it be

du=1/(x+9)*7 dx ok so my answer i got is 1/7(7x+9)(log(7x+9)1)

u=ln(7x+9) du=1/(x+9)dx dv=dx v=x using the IBP formula i get: ln(7x+9)x- (1/7)∫x*(1/x+9) dx is this right or have i made a mistake

Homework Statement \intln(7x+9)dx Homework Equations derivative of ln is 1/x The Attempt at a Solution Well I am just learning IBP so i set u=7x+9 dv=lndx but I am stuck there. How do you know which to make ur u is there a way or is it trial and error Can i split the integral as: ∫ln(7x)+∫9