已知x+1/X=8则X²+1/X²=?
问题描述:
已知x+1/X=8则X²+1/X²=?
答
x²+1/x²
=x²+2+1/x²-2
=(x+1/x)²-2
=8²-2
=64-2
=62
已知x+1/X=8则X²+1/X²=?
x²+1/x²
=x²+2+1/x²-2
=(x+1/x)²-2
=8²-2
=64-2
=62