Bonjour,
a)
15x -3x² -10 +2x -4x² -24x
= -7x² -7x -10
b)
(-6 +6x )(6-2x)
= -36 +12x +36x -12x²
= -12x² + 48x -36
c)
(2x +3x) ( 5x+1)
= 10x² +2x +15x² +3x
= 25x² +5x
d)
(-2x² -2) ( x-2)
= -2x³ +4x² -2x +4
