Réponses

2013-05-14T01:48:19+02:00

( 4x²-9) = (2x - 3) (2x + 3)

( 4x² -12x +9 ) = ( 2x - 3)²

 

Donc on fait :

 

= (2x-3) (2x-3) + (2x-3) (5x-4) - (2x-3)²

= (2x-3) [ 2x-3 + 5x - 4 - 2x + 3 ]

= (2x -3) ( 2x +5x -2x -3 -4 +3)

=( 2x - 3) ( 5x -4 )

 

Voilà

Bon courage