calculus
posted by kim .
evaluate if possible the function at the given values(s) of the independent variable. Simplify the results.
f(x)= square root x+5
(a) f(4)
(b) f(11)
(c) f(8)
(d) f(x+deltax)

Is f(x) sqrt(x+5) or (sqrtx) +5?
I think they mean sqrt (x+5), because is gives integer answers in some cases.
You can't take a square root of a negaive number.
Just plug in the indicated number for x and perform the calculation.
For (b), if x=11, then x + 5 = 15 and sqrt 16 = 4. They probably only want the positive square root.
I would just leave (d) as
sqrt (x + 5 + delta x)