bonjour
g (x) = - 12 x² + 24 x + 27/4
α = - 24 / - 24 = 1
β = - 12 + 24 + 27/4 = 12 + 27/4 = ( 48 + 27) /4 = 75/4
g (x) = 12 ( x - 1 )² + 75/4
g ( 0) = 75/4
- 12 x² + 24 x + 27/4
Δ = 576 - 4 ( - 12 * 27/4 ) = 576 + 324 = 900 = 30 ²
x 1 = ( - 24 - 30 ) / - 24 = - 54/- 24 = 2.25
x 2 = ( - 24 + 30 ) / - 24 ) = - 0.25
g (x) = 0 pour x = 2.25 et - 0.25