Arccotangent
un. 反余切
🗣️ 情景例句
Your brother left his bag of film on the ferryboat.
你哥哥将他的旅行袋遗放在渡船上了。
There is nothing either good or bad, but thinking makes it so.
事情本无好与坏，全在自己怎么想。
It was very old and precious even then.
却使在当时，它也属历史悠久的珍奇之物。