For each function, find the derivtive f'(a) for given value of a

Question

f(x) = sqrt(x+1), a=0

Answer 1

1) you find y' (dy/dx) (f'(x))
2) replace each x by a which equal to one

f(x) = (x+1)^1/2
f'(x) = 1/2 (x+1)^-1/2 (1)
f'(x) = 1 / 2(x+1)
f'(0) = 1/ 2(0+1) = 1/2 = 0.5