x/(x^2-2x+1)=7,求x^2/x^4+x^2+1的值
问题描述：
x/(x^2-2x+1)=7,求x^2/x^4+x^2+1的值
答
x/(x^2-2x+1)=7,(x^2-2x+1)/x=1/7x-2+1/x=1/7x+1/x=15/7x²+1/x²=(x+1/x)²-2=225/49-2=127/49(x^4+x^2+1)/x^2=x²+1+1/x²=127/49+1=176/49x^2/x^4+x^2+1=49/176