bonjour
B (x) = - 200 x² + 1 500 x - 2 200
- 200 x² + 1 500 x - 2 200 = 0
Δ = 1 500 ² - 4 ( - 200 * - 2 200 ) = 2 250 000 - 1 760 000 = 490 000
x 1 = ( - 1 500 - 700 ) / - 400 = - 2 200 / - 400 = 5.5
x 2 = ( - 1 500 + 700 ) / - 400 = - 800 / - 400 = 2
- 200 ( x - 2 ) ( x - 5.5 )
= - 200 ( x² - 5.5 x - 2 x + 11 )
= - 200 x² + 1 100 x + 400 x - 2 200
= - 200 x² + 1 500 x - 2 200