Recent content by jacoleen

one more question, when i separate my variables i get X(x) = Ae(1-lamba2)1/2x + Be-(1-lamba2)1/2x T(t) = Csin(lamba*t)+Dcos(lamba*t), but when I solve it I get all my coefficients equal to zero..are these the right equations?

oh wow, I can`t believe i didnt think of dong that..thanks! :D

Problem: Use separation of variables to solve utt = uxx-u; u(x, 0) = 0; ut(x, 0) = 1 + cos3 x; on the interval (0, pi), with the homogeneous Dirichlet boundary conditions. Question: I know how to use separation of variables, but can`t figure out what to do with the u in the...

OMG..it actually makes sense! Thank you so much for your help! :D

it's equalled to 2?..and so f(2007) = 2*2007!?

is it just -2? (i'm so sorry I logged off btw, my computer overheat :(

* without the negative

the summation divided by x^-2007?

I'm really not getting it.. do i isolate for f(2007) by equating it to the summation? (without the summation term in front)

so my series would just be: Summation of [(-1)n2x2n+1]? I'm not sure how I would work backwards though :|

I was thinking of doing that in the first place, but on another exam there was a similar question and part c was Find f^2007(0) :(

Homework Statement Write the Machlaurin series for : f(x) = (2x)/(1+x2) Homework Equations The Attempt at a Solution I tried finding all the derivatives (aka f(x), f'(x), f''(x), etc..) but the equations started getting longer and longer and would always result in 0 when x=0...

Homework Statement Determine whether the following sequence converges or diverges. If converges, find the limit: a = [1+(2/n)]^n Homework Equations The Attempt at a Solution I thought the limit would be one as inside the brackets at infinity it would be 1^n which would equal...