limx-4{(4-x)/(根号x-2)}求极限 limx-无穷大(x的3字方-2*x+1)/(4*x的3字方－1)求极限_数学解答

limx-4{(4-x)/(根号x-2)}求极限 limx-无穷大(x的3字方-2*x+1)/(4*x的3字方－1)求极限

人气：496 ℃　时间：2020-05-08 02:03:40

解答

lim(x→4)(4-x)/(√x-2)=
lim(x→4)(4-x)(√x+2)/(x-4)=-lim(x→4)(√x+2)=-4
lim(x→∞)(x^3-2x+1)/(4x^3-1)=lim(x→∞)[1-(2/x^2)+(1/x^3)]/(4-1/x^3)=1/4