bonjour
6 x² - 13 x + 6 ≥ 0
6 x² - 13 x + 6 = 0
Δ = 169 - 4 ( 6 * 6 ) = 169 - 144 = 25
x 1 = ( 13 - 25 ) / 12 = - 12/12 = - 1
x 2 = ( 13 + 25 ) / 12 = 36 /12 = 3
tu as les racines donc tu peux répondre
x² - 5 x + 7 < 0
x² - 5 x + 7 = 0
Δ = 25 - 4 ( 1 * 7) = 25 - 28 = - 3
Δ négatif, pas de solution
4 x² - 12 x + 5 ≤ 0
Δ = 144 - 4 ( 4 * 5 ) = 144 - 80 = 64 = 8 ²
x 1 = ( 12 - 8 ) / 8 = 4 /8 = 1/2 = 0.5
x 2 = ( 12 + 8 ) / 8 = 28/8 = 3.5
finis
