5X^2-3 =(25x^2-15)/5=(5x+根号15)(5x-根号15)/5y^2+y+1/4=y^2+y/2+y/2+1/4=y(y+1/2)+(y+1/2)/2=(y+1/2)^2
题目有错吧
是X还是Y,这样根本不能解
5X^-3不能分解y^2+y+1/4=(y+1/2)^2