Not sure if i'm making a double post here not, but got an assignment back, and seems i've gone wrong on just one of the answers. Therefore, I was hoping someone could help me out
Gut feeling, is that i'm approaching the question wrong, but we will see:
From a rectangular sheet of metal measuring 120 mm by 75 mm equal squares of side x are cut from each of the corners. The remaining flaps are then folded upwards to form an open box. Show that the volume of the box is given by:
V = 9000x – 390x2 + 4x3
Find the value of x such that the volume is a maximum.
I wasn't entirely sure how to approach it, and ended up with something like this (see image):
Thanks in advance for any help