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)