Arccosine

Pronunciation: /ɑrk ˈkoʊ saɪn/ ?

A right triangle. One of the angles that is not the right angle is labeled 'theta'. The side adjacent to theta is labeled 'adjacent'. The side opposite the right angle is labeled 'hypotenuse'. Underneath the figure is the equation 'cosin^(-1)(hypotenuse/adjacent) = theta'.
Figure 1: Arccosine

An arccosine is an angle whose cosine is a particular value. The arccosine is a trigonometric function. The arccosine is the functional inverse of the cosine. If adjacent/hypotenuse = cosine(θ) then cosine-1(hypotenuse/adjacent) = θ. Arccosine is written arccosin or cos-1.

Definition: y = cos-1 x if and only if x = cos y.

More Information

  • McAdams, David. Cosine. allmathwords.org. Life is a Story Problem LLC. 2010-08-07.
  • McAdams, David. Inverse of a Function. allmathwords.org. Life is a Story Problem LLC. 2010-08-07.

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Arccosine. 2010-08-07. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/a/arccosine.html.

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2010-08-07: Initial version (McAdams, David.)

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