Question

Find the Taylor series of fx = cosx around a= pi. Find it's radius of convergence

Answer 1

I took this today lol >_< let me see what I can do:\[\cos x = \sum_{k=0}^{\infty} \frac{(-1)^k}{(2k)!} (x- \pi)^{2k}\]

hmm, I didn't study it yet, but I have tried lol, I'm sorry ^_^"

Answer 2

when c = pi

Answer 3

but if c = 0, then (x)^2k