bonjour
( x - 1 )² - 9 x² + 12 x - 4 = 0
x² - 2 x + 1 - 9 x² + 12 x - 4 = 0
- 8 x² + 10 x - 3 = 0
Δ = 100 - 4 ( - 8 * - 3 ) = 100 - 96 = 4 = 2 ²
x 1 = ( - 10 - 2 ) / - 16 = - 12 / -16 = 3 /4
x 2 = ( - 10 + 2 ) / - 16 = - 8 /- 16 = 1 /2
