WolframAlpha增加小数位须手动替换

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1. evaluate x/sqrt(1-2/3 x^2)-tan(x) where x=0.00016129

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输出 0

1. x/sqrt(1-2/3 x^2)-tan(x) /. x=0.00016129

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输出 0

1. ReplaceAll[x/Sqrt[1 - (2 x^2)/3] - Tan[x], {x->0.00016129}]

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输出 0

1. Limit[x/Sqrt[1 - (2 x^2)/3] - Tan[x], {x->0.00016129}]

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输出 0
想要more digits只能手动把x替换

1. 0.00016129/sqrt(1-2/3 0.00016129^2)-tan(0.00016129)

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输出 $3.63845\ldots × 10^{-21}$

问题: WolframAlpha怎么在不手动替换的情况下 增加小数位?

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1. Series[x/Sqrt[1 - (2 x^2)/3] - Tan[x], {x, 0.00016129, 0}]

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输出 $2.710505431213761\times10^{-20}$