Arc cosine
反余弦
?? 詞語(yǔ)組成解析
arc
[ɑ:k]
n. 綜合癥狀;弧（度）;天穹;電弧，弧光。;
vi. 形成拱狀物;循弧線行進(jìn);
abbr. American Red Cross. 美國(guó)紅十字會(huì);
cosine
['k?usain]
n. 余弦;
??? 情景例句
Gemma, sit. Gemma
Gemma,坐,Gemma,
It was eleven o'clock when he finally showed up.
他最后露面時(shí)，已經(jīng)11點(diǎn)鐘了。
But of course, he can learn by himself. He has a book and a dictionary.
但當(dāng)然，他也可以自學(xué)。他有書(shū)和詞典。