lim(x^2-2)/x+5),x→∞求极限_数学解答

lim(x^2-2)/x+5),x→∞求极限

人气：127 ℃　时间：2020-03-08 16:13:26

解答

(x^2-2)/(x+5)
=(x^2-25+23)/(x+5)
=(x^2-25)/(x+5)+23/(x+5)
=(x-5)+23/(x+5)
lim(x^2-2)/x+5)
=lim((x-5)+23/(x+5)),x→∞
=x
=∞
因此极限就是∞