Bonjour,
1.Développer et réduire si possible:
A(x) = - (3 - 2x) = -3+2x
B(x) = 3(4 - 6x) = 12 -18x
C(x) = -2x(5x + 7) = -10x² -14x
D(x) = 8x( x - 3) - (4 - 3x) = 8x² -24x -4 +3x = 8x² -21x -4
2.Développer et réduire si possible:
A(x) = (x + 3) (y + 2) = xy +2x+3y +6
B(x) = (3 - 2x) (4 -x) = 12 -3x -8x +2x² = 2x² -11x +12
C(x) = 2(3 + x) (5 - x) = (6 +2x )(5-x) = 30 -6x +10x -2x² = -2x² +4x +30
D(x) = 2x(1 - x) - (x - 3) (3x + 2) = 2x -2x² -( 3x² +2x -9x -6) =
2x -2x² - 3x² -2x +9x +6 = -5x² +9x +6
3.Développer et réduire si possible:
A(x) = (x - 3) (x + 3) = x² +3x -3x -9 = x² -9
B(x) = (4 - x) (x + 4) = 4x +16 -x² -4x = -x² +16
C(x) = 2(x + 3) + (2x + 3) (2x - 3) = 2x +6 + 4x² -6x+6x -9= 4x² +2x -3