(1+x-2分之一)/2x-4分之x的平方-1

问题描述:

(1+x-2分之一)/2x-4分之x的平方-1

=[(x-2)+1]/(x-2)÷(x+1)(x-1)/2(x-2)
=(x-1)/(x-2)× 2(x-2)/(x+1)(x-1)
=2/(x+1)