bonjour
G = ( 2 x - 3 ) ( 2 x + 3 )
H = ( 2 x - 3 ) ( 2 x + 3 + 7 x + 1 ) = ( 2 x - 3 ) ( 9 x + 4 )
I = ( 5 x + 7 + 2 x + 3 ) ( 5 x + 7 - 2 x - 3 ) = ( 7 x + 10 ) ( 3 x + 4 )
J = ( 5 x + 2 ) + ( 5 x + 2 ) ( 5 x + 2 ) = ( 5 x + 2 ) ( 5 x + 2 + 1 ) = ( 5 x + 2 ) ( 5 x + 3 )