This example is somewhat academic because the ex term will completely dominate the e-x term in any case where the difference between Math.exp() and Math.expm1() + 1 is significant.

这个例子有些呆板，因为在 Math.exp()与 Math.expm1() + 1之间的差别很明显的情况下，常常使用 e x，而不是 e -x。

youdao

Some of these are still listed on The New York Stock Exchange page; on the day that a stock goes ex-dividend, they'll have a little "x" by its price.

有些还在纽约证交所的网页上,股票除息的那一天,股价前面会有个小小的"x"标记

耶鲁公开课 - 金融市场课程节选