Hi there!
f''(4) = -4 means that at x = 4, the second derivative is equal to -4. This is equivalent to the instantaneous rate of change of the graph of f'(x) at x = 4 as well.
Answer:
Step-by-step explanation:
if the second derivative is -4 means that the function is concave down and that at point 4 the function has a maximum
