Sagot :
Bonjour,
A=(4x-8)-(3x-7)+(-2x+3)
=4x-8-3x+7-2x+3
A= -x+2
B=(6x²-5x+7)-(4x²-5x-5)
=6x²-5x+7-4x²+5x+5
B=2x²+12
C=-(3x²-5x+2)+(2x²-2x+8)-(3-2x+2x²)
=-3x²+5x-2+2x²-2x+8-3+2x-2x²
C=-3x²+5x+3
Hello :)
A = (4x - 8) - (3x - 7) + (-2x + 3)
A = 4x - 8 - 3x + 7 - 2x + 3
A = 4x - 3x - 2x + 3 + 7 - 8
A = -x + 2
B = (6x² - 5x + 7) - (4x² - 5x - 5)
B = 6x² - 5x + 7 - 4x² + 5x + 5
B = 6x² - 4x² - 5x + 5x + 7 + 5
B = 2x² + 12
C = -(3x² - 5x + 2) + (2x² - 2x + 8) - (3 - 2x + 2x²)
C = -(3x² - 5x + 2) + 2x² - 2x + 8 - 3 + 2x - 2x²
Les x² en gras s'annulent
C = -(3x² - 5x + 2) - 2x + 8 - 3 + 2x
C = -(3x² - 5x + 2) + 8 - 3
C = -3x² + 5x - 2 + 8 - 3
C = -3x² + 5x + 3
Bonne journée :)