已知x2-2=0,求代数式(x-1)2/x2-1+x2/x+1的值.

问题描述:

已知x2-2=0,求代数式(x-1)2/x2-1+x2/x+1的值.
所有在x后面的2是平方的意思.

x²-2=0x²=2(x-1)²/(x²-1)+x²/(x+1)=(x-1)²/(x+1)(x-1)+x²/(x+1)=(x-1)/(x+1)+x²/(x+1)=(x-1+x²)/(x+1)=(x-1+2)/(x+1)=(x+1)/(x+1)=1