Sagot :
A) C’(x) = 4x _2xe^-2x+3
B) C(0) = 0
C’(1.5) = 6 - 3 = 3
Pour 0 articles, le cout total = 0 (c(0) =0)
Pour 1.5 centaines d’article, un cout marginal est de 3
1) CM (x) = (2x^2 + xe^-2x+3) / x
2) CM’(x) = [x(4x_2xe^-2x+3) - (2x^2 + xe^-2x+3)] /x^2
= (4x^2 _ 2x^2 e^-2x+3 - 2x^2 +xe^-2x+3) / x^2
= [2x^2 +e^-2x+3 ( -2x^2 +x)]/x^2
3) 1 - e^2x-3 = 0
e^2x-3 = 1
2x-3 = ln(1) = 0
x = 3/2
4) 1-e^2x-3 >0
e^2x-3<1
2x-3 < 0
x<3/2
B) C(0) = 0
C’(1.5) = 6 - 3 = 3
Pour 0 articles, le cout total = 0 (c(0) =0)
Pour 1.5 centaines d’article, un cout marginal est de 3
1) CM (x) = (2x^2 + xe^-2x+3) / x
2) CM’(x) = [x(4x_2xe^-2x+3) - (2x^2 + xe^-2x+3)] /x^2
= (4x^2 _ 2x^2 e^-2x+3 - 2x^2 +xe^-2x+3) / x^2
= [2x^2 +e^-2x+3 ( -2x^2 +x)]/x^2
3) 1 - e^2x-3 = 0
e^2x-3 = 1
2x-3 = ln(1) = 0
x = 3/2
4) 1-e^2x-3 >0
e^2x-3<1
2x-3 < 0
x<3/2