Bonjour,
Factoriser:
J= 2(3x-4)(x-7)+x²-14x+49
J= 2(3x-4)(x-7)+(x-7)(x-7)
J= (x-7)[ 2(3x-4)+x-7 ]
J= (x-7)(6x-8+x-7)
J= (x-7)(7x-15)
K= (2x-5)(2x+1)+(10-4x)(2x-3)
K= (2x-5)(2x+1)+ 2(5-2x)(2x-3)
K= (2x-5)(2x+1) - 2(2x-5)(2x-3) ****changement de signes
K= (2x-5)[ (2x+1-2(2x-3) ]
K= (2x-5)(2x+1-4x+6)
K= (2x-5)(-2x+7)
K= - (2x-5)(2x-7)
L= x²+8x+16-(x+4)(2x+1)
L= (x+4)(x+4) -(x+4)(2x+1)
L= (x+4)(x+4-2x-1) **** changement de signe
L= (x+4)(-x+3)
L= - (x+4)(x-3)
