Sagot :
A = (x-3)^2+3(6x-4)= x^2-6x+9+18x-12=x^2+12x-3
B=(x-1)(x+1)+1 = x^2-1+1=x^2
C= (x-8)(2x+3)-(4x+3)^2=2x^2+3x -16x-24 -16x^2-24x-9 = -14x^2-13x-33
A = (x - 3)² + 3(6x - 4)
A = x² - 6x + 9 + 18x - 12
A = x² + 12x - 3
B = (x - 1)(x + 1) + 1
B = x² + x - x - 1 + 1
B = x²
C = (x - 8)(2x + 3) - (4x + 3)²
C = 2x² + 3x - 16x - 24 - (16x² + 24x + 9)
C = 2x² - 13x - 24 - 16x² - 24x - 9
C = - 14x² - 37x - 33