答:
x²-x-1=0
x²=x+1
两边同时除以x:x-1-1/x=0,x-1/x=1
两边平方得:x²-2+1/x²=1,x²+1/x²=3
1)
-x³+2x²+2002
=-(x+1)x+2x²+2002
=x²-x+2002
=1+2002
=2003
2)
x²+1/x²+2014=3+2014=2017
答:
x²-x-1=0
x²=x+1
两边同时除以x:x-1-1/x=0,x-1/x=1
两边平方得:x²-2+1/x²=1,x²+1/x²=3
1)
-x³+2x²+2002
=-(x+1)x+2x²+2002
=x²-x+2002
=1+2002
=2003
2)
x²+1/x²+2014=3+2014=2017