已知:x²+3x+1=0,求:x²+x负二次方的值

2025-03-13 03:00:03
推荐回答(1个)
回答1:

x^2+3x+1=0,
x+3+1/x=0
x+1/x=-3
x^2+x^(-2)
=x^2+2+1/x^2-2
=(x+1/x)^2-2
=(-3)^2-2
=9-2
=7