x的平方－２（m-n)x+n的平方＝２mn
热心网友
x^2-2(m-n)x+n^2=2mnx^2-2(m-n)x+n^2-2mn+m^2=m^2x^2-2(m-n)x+(m-n)^2=m^2(x-m+n)^2=m^2x-(m-n)=±mx1=2m-nx2=-n
热心网友
x^2-2(m-n)x+n^2=2mnx^2-2(m-n)x+n^2-2mn+m^2=m^2x^2-2(m-n)x+(m-n)^2=m^2(x-m+n)^2=m^2x-(m-n)=±mx=2m-n 或 2=-n
热心网友
x^2 - 2*(m-n)x + n^2 = 2mn== [x - (m-n)]^2 = m^2== x - (m-n) = m, or, x - (m-n) = -m== x = 2m-n, or, x = -n