求教湘教版八年级下册数学新课标课程基础训练答案
问题描述:
求教湘教版八年级下册数学新课标课程基础训练答案
题目是已知x²-5x+1=0,求(x^4+1)/x²的值
答
x²=5x-1,(x^4+1)/x²=((5x-1)^2+1)/(5x-1)=(25x^2-10x+2)/(5x-1)=(25(5x-1)-10x+2)/(5x-1)=(25(5x-1))/(5x-1)-2(5x-1)/(5x-1)=23