bonjour
f (x) = 4 ( x - 2 ) ( x + 4 )
f ( x) = ( 4 x - 8 ) ( x + 4 )
f ( x) = 4 x² + 16 x - 8 x - 32
f ( x) = 4 x² + 8 x - 32
Δ = 8 ² - 4 ( 4 * - 32 ) = 64 - 512 = - 448
Δ < 0 donc pas de solutions
g ( t) = - 3 ( t + 2.5 ) ( t - 1/3 )
g ( t) = ( - 3 t - 7.5 ) ( t - 1 /3 )
g ( t ) = - 3 t² + 3 t / 3 - 7.5 t + 7.5/3
g ( t ) = - 3 t² - 6.5 t + 2.5
Δ = 6.5² - 4 ( - 3 * 2.5 ) = 42.25 + 30 = 72.25 = 8.5²
x 1 = ( 6.5 - 8.5 ) / - 6 = 2/6 = 1 /3
x 2 = ( 6.5 + 8.5 ) / - 6 = - 15/6 = - 5/2
