Efectuati:
a) (x-3)(x+2)+(2x+1)(3x-2)-2x(x+1)
b)(x-6)(2x+5)-(x+2)(x+3)+(3-x)(x+4)
c)(a+b)(a+3b)+(2a-3b)(a+2b)-(a-b)(3a+b)
d)(x^2+x)(x+1)-x^2(2+x)+(x+2)(3+x^2)-6

rezolvarea este in atasament
sper sa intelegi ce am scris. daca este ceva neclar imi poti spune

a. [x-3][x+2]+[2x+1][3x-2]-2x[x+1]= x²+2x-3x-6+6x²-4x+3x-2-2x²+2x = x²+2x-6+6x²-4x-2-2x²+2x = 5x²-8
b.[x-6][2x+5]-[x+2][x+3]+[3-x][x+4] = 2x²+5x-12x-30-x²+3x+2x+6+3x+12-x²-4x = -3x-12
c. [a+b][a+3b]+[2a-3b][a+2b]-[a-b][3a+b] = a²+3ab+ab+3b²+2a²+4ab-3ab-6b²-3a²+ab-3ab-b² = -3ab-4b²
d. [x²+x][x+1]-x²[2+x]+[x+2][3+x²]-6 = x³+x²+x-2x²-x³+3x+x³+6+2x²-6 = 2x²+4x+x³