# Taylor series expansion

## Homework Statement

I am trying to find the Tn(x) for sqrt[x] centered at a=1

## The Attempt at a Solution

right now i have
f'(x)=1/2x^-1/2
f''(x)=-1/4x^-3/2
f'''(x)=3/8x^-5/2
f''''(x)=-15/16x^-7/2
f'(1)=1/2
f''(1)=-1/4
f'''(1)=3/8
f''''(1)=-15/16

how do i find the coefficient for the nth term?? i keep getting stuck
i tried n/2+1/(-2)^n.. doesn't work
or 1/(-2)^n*(n/2-1)....fail