Réponse :
bonjour
( 6 x + 1 )x = ( 3 x + 2 ) ( 6 x + 1 )
( 6 x + 1 )x - ( 3 x + 2 ) ( 6 x + 1 ) = 0
( 6 x + 1 ) ( x - 3 x - 2 ) = 0
( 6 x + 1 ) ( - 2 x - 2 ) = 0
x = - 1/6 ou - 1
( 2 x - 1 )² - ( x + 2 )² = 0
( 2 x - 1 + x + 2 ) ( 2 x - 1 - x - 2 ) = 0
( 3 x + 1 ) ( x - 3 ) = 0
x = - 1/3 ou 3
3 x ( x ² + 1 ) = x² ( x² + 1 )
3 x ( x² + 1 ) - x² ( x ² + 1 ) = 0
( x² + 1 ) ( 3 x - x² ) = 0
x² + 1 = 0 ⇔ x² = - 1 donc pas de solution
3 x - x² = 0 ⇔ - x ( - 3 + x ) = 0 ⇔ x = 0 ou 3
