Răspunsuri

2014-09-19T09:18:59+03:00
(3x+1)²-(6x-2)²
se aplica formula a²-b²=(a-b)(a+b)
(3x+1-6x+2)(3x+1+6x-2)=(-3x+3)(9x-1)=-3(x+1)(9x-1)
(5x-1)²+(2x-1)(2x+1)=25x²-10x+1+4x²-1=29x²-10x=x(29x-10)
(2x-1)(5x+3)=10x²-5x+6x-3=10x²+x-3