arccos

== English == === Etymology === From arc- +‎ cos. === Noun === arccos (plural arccoses) Abbreviation of arccosine. arccos ⁡ ( 1 2 ϕ ) = 2 π 5 {\displaystyle \arccos \left({1 \over 2\phi }\right)={2\pi \over 5}} ==== See also ==== arcsin arctan === Anagrams === corsac