Surface are of a rectangular prism = 2(l x w + l x h + w x h) = 2(10 x 3 + 10x + 3x) = 2(30 + 13x) = 60 + 26x
Volume of a rectangular prism = l x w x h = 10 * 3 * x = 30x
Since surface area = volume
60 + 26x = 30x
4x = 60
x = 15 in
T = 5, so after 5 years
p(t) = t^3 - 14t^2 + 20t + 120
Take derivative to find minimum:
p’(t) = 3t^2 - 28t + 10
Factor to solve for t:
p’(t) = (3t - 2)(t - 5)
0 = (3t - 2)(t - 5)
0 = 3t - 2
2 = 3t
2/3 = t
Plug 2/3 into original equation, this is a maximum. We want the minimum:
0 = t - 5
5 = t
Plug back into original:
5^3 - 14(5)^2 + 20(5) + 120
125 - 14(25) + 100 + 120
125 - 350 + 220
- 225 + 220
p(5) = -5
Answer:
2) Constraints can be used to model different variables that cannot equal zero. They can be used in many different cases. For example, modeling money or a ball being dropped.
Step-by-step explanation:
