Bonjour,
Factoriser:
A=9(x+4)-(x-4)² ** possible erreur d'écriture du 2 e terme).
A=9x+36 -( x²-4x-4x+16)
A= 9x+36-x²+8x-16
A= -x²+17x+20
Δ= (17)²-4(-1)(20= 369 > 0; 2 solutions
x1= (-17-√369)/2(-1)=(-17-√(9x41))/-2= (-17-3√41)/-2= (17+3√41)/2
x2= (-17+3√41)/-2= (17-3√41)/2
A= (x-x1)(x+x2)
B=(x-8)²-144
B= (x-8)²-12²
B= (x-8-12)(x-8+12)
B= (x-20)(x+4)
C=(14x-39)²-3(14x-39)
C= (14x-39)(14x-39-3)
C= (14x-39)(14x-42)
C= 14(14x-39)(x-3)
D=(9x-4)²-121
D= (9x-4)²-11²
D= (9x-4-11)(9x-4+11)
D= (9x-15)(9x+7)
D= 3(3x-5)(9x+7)
E=(5x-6)²-5x+6
E= (5x-6)²-(5x-6)
E= (5x-6)(5x-6-1)
E= 5x-6)(5x-7)
