Lim[(3x)^1/2] * e^(cos(8pi/ x) ( x-->+0) 求极限?
问题描述:
Lim[(3x)^1/2] * e^(cos(8pi/ x) ( x-->+0) 求极限?
答
∵ cos(8π/x) ≤ 1 (x≠0) ,e^x 单调递增;
∴ 0 ∴ 0 ∵ lim(x->0+) [(3x)^1/2] = 0 ,由夹逼定理:
∴ lim(x->0+) [(3x)^1/2] * e^(cos(8π/x) = 0