Sagot :
Bonjour.
Factoriser :
A = 5x(x-2)-x(x+2)
A = x(5(x-2)-(x+2))
A = x(5x-10-(x+2))
A = x(5x-10-x-2)
A = x(4x-10-2
A = x(4x-12)
A = x×4(x-3)
A = 4x(x-3)
B = (2x-3)2-(6x-7)(2x-3)
B = 2(2x-3)-(6x-7)(2x-3)
B = (2x-3)(2-(6x-7))
B = (2x-3)(2-6x+7)
B = (2x-3)(9-6x)
B = (2x-3)×3(3-2x)
B = 3(2x-3)(3-2x)
C = 4(2a-5)2-(2a-5)
C = 8(2a-5)-(2a-5)
C = 7(2a-5)
Développer puis réduire :
A = 5x(x-2)-x(x+2)
A = 5x²-10x-x(x+2)
A = 5x²-10x-x²-2x
A = 4x²-10x-2x
A = 4x²-12x
B = (2x-3)2-(6x-7)(2x-3)
B = (2x-3)(2-(6x-7)
B = (2x-3)(2-6x+7)
B = (2x-3)(9-6x)
B = (2x-3)(-6x+9)
B = (2x-3)(-3(2x-3))
B = (2x-3)(-3)(2x-3)
B = (2x-3)²(-3)
B = -(2x-3)²3
B = -3(2x-3)²
B = -3(4x²-12x+9)
B = -12x²+36x-27
C = 4(2a-5)2-(2a-5)
C = (4×2-1)(2a-5)
C = (8-1)(2a-5)
C = 7(2a-5)
C = 14a-35