Répondre :
A(x) = (x-2)(2x+5)+4(x-2)(x-1) = (x-2)(2x+5+4x-4) = (x-2)(6x+1)
A(x) = x²-4x+3 = x^2 -4x + 4 -4 +3= (x^2 -4x + 4)-1=(x-2)^2 -1
A(x) = x²-4x+3 = x^2 -4x + 4 -4 +3= (x^2 -4x + 4)-1=(x-2)^2 -1