Răspuns:
[tex]\bf a) ~~2x(x + 1) - 5(x + 1) = (x + 1)\cdot(2x - 5)[/tex]
[tex]\bf b) ~~4(2x + 3) - x(2x + 3) + (2x + 3)(x + 1) =[/tex]
[tex]\bf (2x + 3)\cdot (4 - x + x + 1) = 5\cdot (2x + 3)[/tex]
[tex]\bf c)~~ 6x(3x - 7) + 5(3x - 7) = (3x - 7)\cdot(6x + 5)[/tex]
[tex]\bf d)~~14x(2x - 1) - 7(2x - 1) = (2x-1)\cdot(14x-7)[/tex]
[tex]\bf (2x-1)\cdot7\cdot(2x-1)=7\cdot(2x-1)^2[/tex]
[tex]\bf e) ~~10x(x + 6) + 5(x + 6)^2 = (x+6)\cdot[10x+5(x+6)][/tex]
[tex]\bf (x+6)\cdot5\cdot(2x+x+6)=5\cdot(x+6)\cdot(3x+6)[/tex]
[tex]\bf 5\cdot(x+6)\cdot3\cdot(x+2)= 15\cdot(x+6)\cdot(x+2)[/tex]
[tex]\bf f)~~ 12(x - 3)^2 + 6x(x -3) = 6(x-3)\cdot[2(x-3)+x]=[/tex]
[tex]\bf 6(x-3)\cdot(2x-6+x)=6(x-3)\cdot(3x-6)=[/tex]
[tex]\bf 6(x-3)\cdot3\cdot(3x-6)=18\cdot(x-3)\cdot(x-2)[/tex]
[tex]\bf g)~~21x(3x - 1) - 7(3x - 1)^2 = 7(3x-1)\cdot[3x-(3x-1)]=[/tex]
[tex]\bf 7(3x-1)\cdot(3x-3x+1)= 7\cdot(3x-1)[/tex]
[tex]\bf h) ~~24x(4x + 3) - 8(4x + 3)^2 =[/tex]
[tex]\bf 8(4x + 3)\cdot[3x - (4x + 3)] = 8(4x + 3)\cdot(3x - 4x - 3) =[/tex]
[tex]\bf 8\cdot(4x + 3)\cdot(-x - 3)[/tex]
[tex]\bf i)~~ (2x+5)[3(x-2)-2(x-4)]+2(2x+5)=[/tex]
[tex]\bf (2x+5)\cdot[3(x-2)-2(x-4)+2] =[/tex]
[tex]\bf (2x+5)\cdot(3x-6-2x+8+2) = (2x+5)\cdot(x+4)[/tex]
[tex]==pav38==[/tex]
