Question

The functions f and g are differentiable and h (x) = g (f (x)). Evaluate (g o f o h) '(6), given that:
f(4) = 4 f ' (4) = 4
f(5) = 4, f ' (5) = 5
f(6) = 4, f ' (6) = 5
g(4) = 4, g ' (4) = 5
g(5) = 6, g ' (5) = 5
g(6) = 5, g ' (6) = 5
h(4) = 4, h ' (4) = 4
h(5) = 5, h ' (5) = 6
h(6) = 5, h ' (6) = 4