a)(x la adoua+2x+1)(x+1)=x la a treia + x la adoua +2x la adoua +2x+x+1=
=x la a treia+2x la a doua + 3x + 1
b)(9x la a doua -6x+1)(3x-1)+(9x la a doua+6x+1)(3x+1)=27x la a treia -9 x la a doua -18x la a doua +6x+3x-1+27x la a treia -9x la a doua +18x la a doua+6x+3x+1=54x la a treia-18x la a doua+18x =3(18x la a treia -x la a doua +x)
c)???