Raymond B. answered 06/24/21
Math, microeconomics or criminal justice
C(x) = 50 + 350x + 0.09x^2
C(100) = 50 + 350(100)+ 0.09(100)^2 = 50+ 35,000+ .09(10000)
= 35,050 + 900= 35,950
C'(x) = 350 + 0.18x
C'(100) = 350 + 0.18(100) = 350 + 18 = 368
C(101) = 50 + 350(101) + 0.09(101)^2 = 50 + 35,350 + 909 = 35,400+ 909 = 36,309
C(100)+C'(100) = 35,950 + 368 = 36,318 which is close to C(101), just 9 more.
C(100) is the cost of 100, C'(100) is the cost of one more, if the cost function were linear. For small x, it's almost linear.