C'(x)= 60sqroot(x+1) FC= 340

Question

R'(x)=80x

Finding profit or loss from production and sale of 3 units and 8 units.

C(x)=40(x+1)^3/2+300
R(x)=40x^2

P(x)= R(x)-C(x)

Are my integrations correct and how would i find profit or loss?

INtegrations are correct.

Profit= 40x^2 - 40(x+1)^3/2-300

Put in x=3, or x=8