初三数学题（分式化简)
问题描述：
初三数学题（分式化简)
化简：(2009a/a^2-2a+1)/[(1/a-1)+1]
答
(2009a/a^2-2a+1)/[(1/a-1)+1] =2009a/(a-1)^2/[(1+a-1)/(a-1)] =2009a/(a-1)^2*(a-1)/a =2009/(a-1)