lim(x趋向于0+)x^tanx 求极限?

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lim(x趋向于0+)x^tanx求极限?lim(x趋向于0+)x^tanx求极限?lim(x趋向于0+)x^tanx求极限?lim(x趋向于0+)x^tanx=e^lim(x趋向于0+)lnx^ta

lim(x趋向于0+)x^tanx 求极限?
lim(x趋向于0+)x^tanx 求极限?

lim(x趋向于0+)x^tanx 求极限?
lim(x趋向于0+)x^tanx
=e^lim(x趋向于0+)lnx^tanx
=e^lim(x趋向于0+)lnx*tanx
=e^lim(x趋向于0+)lnx/cotx (∞/∞)
=e^lim(x趋向于0+)(1/x)/(-csc^2x)
=e^lim(x趋向于0+)-sinx
=e^0
=1

洛必达法则;取ln对数,得(ln(x)/cot(x)),上下求导得 -(sin²x/x²)所以结果是 -1