bonjour
C ( x) = x² - 10 x + 500
R (x) = 50 x
B (x) = 50 x - ( x² - 10 x + 500 ) = 50 x - x² + 10 x - 500 = - x² + 60 x - 500
C ( 50) = 50² - 50 x 10 + 500 = 2 500 - 500 + 500 = 2 500
R ( 50 ) = 50 x 50 = 2 500
B (50) = - ( 50 )² + 60 * 50 - 500 = 2 500 + 3000 - 500 = 5 000
- x² + 60 x - 500 = 364
- x² + 60 x - 500 - 364 = 0
- x² + 60 x - 864 = 0
Δ = 60 ² - 4 ( - 1 * - 864) = 3 600 - 3 456 = 144 = 12 ²
x 1 = ( - 60 + 12 ) / - 2 = - 48 / - 2 = 24
il doit en fabriquer 24
- 24 ² + 60 * 24 - 500 = - 576 + 1 440 - 500 = 364
