Answer: B
Step-by-step explanation:
First find the critical points of <em>f</em> :



so the point (1, 0) is the only critical point, at which we have

Next check for critical points along the boundary, which can be found by converting to polar coordinates:

Find the critical points of <em>g</em> :



where <em>n</em> is any integer. We get 4 critical points in the interval [0, 2π) at




So <em>f</em> has a minimum of -7 and a maximum of 299.
I think that the best answer is A
Answer:
Part A:
P(x)=15x^4+30x^3-50
Part B:
P(4)=$4270
Step-by-step explanation:
Part A:
In order to find the profit function P(x) we have to integrate the P'(x)
P'(x)=x(60x^2+90x)
P'(x)=60x^3+90x^2

P(x)=15x^4+30x^3+C
when x=0, C=-50
P(x)=15x^4+30x^3-50
Part B:
x=4
P(x)=15x^4+30x^3-50
P(4)=15*4^4+30*4^3-50
P(4)=$4270
Profit from selling 400 pounds is $4270