bonjour
a = ( 6 t - 1 )²
b = ( 3 y + 4 )²
c = ( 3 x + 5 + x + 8 ) ( 3 x + 5 - x - 8 ) = ( 4 x + 13 ) ( 2 x - 3 )
d = ( 6 x - 2 )²
