1/5x^2y-x^4-y^2/100
问题描述:
1/5x^2y-x^4-y^2/100
答
1/5x^2y-x^4-y^2/100
原式=-(x^4-2*x^2*1/10y+y^2/100)
=-(x^2-y/10)^2