bonsoir
"je comprends rien" un peu exagéré non ?
a = 2 x² - x - 15 + 3 x
a = 2 x² + 2 x - 15
b = (x² + x ) ( 4 - 2 x )
b = 4 x² - 2 x ³ + 4 x - 2x ²
b = - 2 x ³ + 2 x² + 4 x
a = ( 2 x + 1 ) ( 4 - x + 4 x - 1 )
a = ( 2 x + 1 ) ( 3 x + 3 )
b = ( 3 - 2 x ) ( x + 5 - 3 + 2 x )
b = ( 3 - 2 x ) ( 3 x + 2 )
continue
