bonjour
x² - 2 ( m + 2 )x + m² + 4 m - 5 = 0
Δ = ( - 4 - 2 m )² - 4 ( 1 * - 5 + 4 m + m²)
Δ = ( - 4 - 2 m)² - 4 ( - 5 + 4 m + m² ) = 36
x ₁ = - ( -4 - 2 m - √36) / 2 = ( 4 + 2 m + 6)/2 = m + 5
x 2 = ( - 4 - 2 m + √36) /2 = ( 4 + 2 m - 6 )/2 = m - 1
S [ - 1 + m ; m + 5 ]
