в) z^3+21+3z+7z^2=z^2(z+7)+3(z+7)=(z^2+3)(z+7)
г) z-3z^2+z^3-3=z^2(z-3)+(z-3)=(z^2+1)(z-3)
в) 18a^2+27ab+14ac+21bc=9a(2a+3b)+7c(2a+3b)=(9a+7c)(2a+3b)
г) 2x^2yz-15yz-3xz^2+10xy^2=2xy(xz+5y)-3z(xz+5y)=(2xy-3z)(xz+5y)
z-3*z^2+z^3-3 = (z-3)*(z^2+1)
18*a^2+27*a*b+14*a*c+21*b*c = (3*b+2*a)*(7*c+9*a)
2*x^2*y*z-15*y*z-3*x*z^2+10*x*y^2 = -(3*z-2*x*y)*(5*y+x*z)
в) z^3+21+3z+7z^2=z^2(z+7)+3(z+7)=(z^2+3)(z+7)
г) z-3z^2+z^3-3=z^2(z-3)+(z-3)=(z^2+1)(z-3)
в) 18a^2+27ab+14ac+21bc=9a(2a+3b)+7c(2a+3b)=(9a+7c)(2a+3b)
г) 2x^2yz-15yz-3xz^2+10xy^2=2xy(xz+5y)-3z(xz+5y)=(2xy-3z)(xz+5y)