bonjour
( 2 x- 3 ) ( 3 x + 7 ) - 2 x + 3
= ( 2 x - 3 ) ( 3 x + 7 ) - 1 ( 2 x - 3 )
= ( 2 x - 3 ) ( 3 x + 7 - 1 )
= ( 2 x - 3 ) ( 3 x + 6 )
= 3 ( 2 x - 3 ) ( x + 2 )
( 5 x - 4 )² - 5 x +4
= ( 5 x - 4 )² - 1 ( 5 x - 4 )
= ( 5 x - 4 ) ( 5 x - 4 - 1 )
= ( 5 x - 4 ) ( 5 x - 5 )
= 5 ( 5 x - 4 ) ( x - 1 )
( 2 x + 7 )² - 2 x - 7 + ( 3 x - 1 ) ( 2 x + 7 )
= ( 2 x + 7 )² - 1 ( 2 x + 7 ) + ( 3 x - 1 ) ( 2 x + 7 )
= ( 2 x + 7 ) ( 2 x + 7 - 1 + 3 x - 1 )
= ( 2 x + 7 ) ( 5 x + 5 )
= 5 ( 2 x + 7 ) ( x + 1 )
fais le dernier