化简极限函数求值limx→64 [x^(1/3)-4]/[x^(1/2)-8]

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化简极限函数求值limx→64[x^(1/3)-4]/[x^(1/2)-8]化简极限函数求值limx→64[x^(1/3)-4]/[x^(1/2)-8]化简极限函数求值limx→64[x^(1/3)-

化简极限函数求值limx→64 [x^(1/3)-4]/[x^(1/2)-8]
化简极限函数求值
limx→64 [x^(1/3)-4]/[x^(1/2)-8]

化简极限函数求值limx→64 [x^(1/3)-4]/[x^(1/2)-8]
limx→64 [x^(1/3)-4]/[x^(1/2)-8]
令x^(1/6)=t
x→64,即t→2
原式=lim(t→2)[t²-4]/(t³-8)
=lim(t→2)(t-2)(t+2)/(t-2)(t²+2t+4)
=lim(t→2)(t+2)/(t²+2t+4)
=4/12
=1/3