x/x^2-3x+1=1,求x^2/x^4-9x^2+1
问题描述:
x/x^2-3x+1=1,求x^2/x^4-9x^2+1
x+1/x=4是怎样来的?x^4-9x^2+1/x^2=x^2+1/x^2-9这一步我也不知道怎么得出来的请详细教我,
答
x/(x^2-3x+1)=1,x=x^2-3x+1x^2+1=4x,两边同除以x,【由x/(x^2-3x+1)=1,x≠0】x+1/x=4两边平方x^2+1/x^2+2*x*1/x=16x^2+1/x^2+2=16x^2+1/x^2=14;x^2/(x^4-9x^2+1)=1/(x^2-9+1/x^2),【上下同除以x^2】=1/(14-9)=1/5...为什么这有什么规律吗两边同除以x,x^2+1=4x,这步是怎样算出来的?x=x^2-3x+1
移项
x+3x=x^2+1
x^2+1=4x