bonsoir
3 x² + 4 x = 0
x ( 3 x + 4 ) = 0
x = 0 ou - 4/3
4x² + 7 = 0
4 x² = - 7
pas de solution dans R
x² + 2 x + 1 = 0
( x + 1 )² = 0
x = - 1
2 x² = x
2 x² - x = 0
x ( 2 x - 1 ) = 0
x = 0 ou 1 /2
7 x² - 14 = 0
7 x² = 14
x² = 2
x = √2 ou - √2
2 ( 5 x +7 ) ( - 3 x + 2 ) = 0
x = - 7/5 ou 2/3