问题补充:
已知x²-3x+1=0,则x+x负一次方= ,x²+x负二次方= ,x四次方+x负四次方=
答案:
1.x^2-3x+1=0
x^2+1=3x
x+ 1/x=3
①x+1/x^2=(x=1/x)^2-2=7
②x^4+1/x^4=(x^2+1/x^2)-2=47
======以下答案可供参考======
供参考答案1:
x^2-3x+1=0
x-3+1/x=0
x+1/x=3
x^2+1/x^2
=(x+1/x)^2-2
=3^2-2
=7x^4+1/x^4
=(x^2+1/x^2)^2-2
=7^2-2
=47