А) 3ab+ a^2 = a(3b+a) б) 4b^3 - 3b^5 = b^3(4-3b^2) в) -15a^3b - 5ab^2 - 10a^2b^4 = -5ab(3a^2-b-2ab^3) г) 5y(x+y) + x(x+y) = 5yx+5y^2+x^2+xy=6xy+6x^2=6x(y+x) д) 2a-ax+2b-bx = (2a+2b)(-ax-bx) е) 20m^2 - 5n^4 = 5(4m^2-n^2)=5(2m-n)(2m+n) ж) -5x^2 +20x-20 = -5(x^2-4x+4)=-5(x-2)^2 з) 64a^3 -b^3 = (4a-b)(16a^2+4ab+b^2)