упростить: mn^2-n^2+mn-n; 1\xy(x^3y-2xy^3-x^2y^2);

Question

упростить: mn^2-n^2+mn-n; 1\xy(x^3y-2xy^3-x^2y^2);

Answer 1

mn^2-n^2+mn-n=n^2(m-n)+n(m-n)=(n^2+n)(m-n)=n(n+1)(m-n)

 

1\xy(x^3y-2xy^3-x^2y^2)=1\xy *xy(x^2-2y^2-xy)=x^2-2y^2-xy=

x^2-y^2-y^2-xy=(x-y)(x+y)-y(x+y)=(x+y)(x-y-y)=(x+y)(x-2y)