Answer:
A is f ", B is f, C is f '.
Step-by-step explanation:
Your answer is correct. B is the original function f. It has a local maximum at x=0, and local minimums at approximately x=-3/2 and x=3/2.
C is the first derivative. It crosses the x-axis at each place where B is a min or max. C itself has a local maximum at approximately x=-3/4 and a local minimum at approximately x=3/4.
Finally, A is the second derivative. It crosses the x-axis at each place where C is a min or max.
The total surface area of this prism is 480.
Bu using Pythagoras theorem
(x^2)+(21)^2=(75)^2
Therefore. 5625-441=(x)^2
X^2=5184
Therefore x=72
Third side length=72 units