-x^3+x^2y-1/4xy^2(m+n)^2-4(m+n-1) (a^2+b^2)^2=4a^2b^2 16x^4-72^2+81 (x^2-2x)^2+2(x^2-2x)+1

问题描述:

-x^3+x^2y-1/4xy^2
(m+n)^2-4(m+n-1) (a^2+b^2)^2=4a^2b^2 16x^4-72^2+81 (x^2-2x)^2+2(x^2-2x)+1

-x^3+x^2y-1/4xy^2 =-x/4 (4x²-4xy+y²)=-x/4 (2x-1)²(m+n)^2-4(m+n-1) =(m+n)²-4(m+n)+4=(m+n-2)²(a^2+b^2)^2-4a^2b^2 =(a²+2ab+b²)(a²-2ab+b²)=(a+b)²(a-b)...