Definition

A mathematical function that gives the angle whose cosine is a given number. It is the inverse of the cosine function.

Example

To find the angle, you can use the arccosine of the cosine value.

Conversation

Have you ever heard of the arccosine function in math?

Yeah, it's the inverse of the cosine, right?

Exactly! I always get confused between sine and arccosine.

It can be tricky, but once you get the hang of it, it's easier.

Synonyms & Antonyms

Root Explanation

Arccosine is formed from "arc-" (from Latin *arcus*, meaning bow or curve) and "cosine" (from Latin *cosinus*, meaning complementary angle). The term refers to the angle whose cosine is a given number, thus relating to the curve of the unit circle.

Memory Tip

Think of 'arc' as a curve and 'cosine' as a function related to angles — arccosine is the angle that corresponds to a specific cosine value.

Visually Confused Words