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arc cosine

noun
  1. Trigonometry. the angle, measured in radians, that has a cosine equal to a given number. Abbreviation: arc cos; Symbol: cos−1

Origin of arc cosine

First recorded in 1905–10
Also called inverse cosine.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
arc cosine in Science

arc cosine

  1. The inverse of the cosine function.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.