计算极限x→2,limx²－3x＋2／x²－4,
问题描述：
计算极限x→2,limx²－3x＋2／x²－4,
答
原式=x→2,lim（x-1)(x-2)/(x-2)(x+2)
=x→2,lim（x-1)/(x+2)
=(2-1)/(2+2)
=1/4
答
运用洛必达法则可得：x→2,limx²－3x＋2／x²－4=1/4
答
(x²-3x+2)/(x²-4)
=(x-1)(x-2)/(x+2)(x-2)
=(x-1)/(x+2)
limx->2 (x-1)/(x+2)=1/4