-(x+3) (2x-3) (inférieure ou égale à) -2(x-1)
(x+3)(2x-3) ≥ 2(x-1)
2x² -3x +6x - 9 ≥2x-2
2x² +x ≥ 7
x² + x/2 ≥ 7/2
(x+ 1/4)² - 1/16 ≥ 7/2
(x+1/4)² ≥1/16 + 56/16
(x+1/4)² ≥57/16
x+1/4 ≥ rac(57)/4 ou x +1/4 ≤ -rac(57)/4
x ≥rac(57)/4 - 1/4 ou x ≤ -rac(57)/4 -1/4
