更新1:
Nevermind. I just forgot 1 - sin^2 can be factored.. derp
Nevermind. I just forgot 1 - sin^2 can be factored.. derp
收錄日期: 2021-04-18 15:37:56
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20161004234512AArwT24