# Tangent

Pronunciation: /ˈtæn.dʒənt/ Explain

 Click on the blue points and drag them to change the figure For what angle is the tangent zero? Manipulative 1 - Tangent Created with GeoGebra.

Tangent is defined to be equal to the length of the side opposite the angle divided by the length of the side adjacent to the angle of a right triangle. Given a tangent value, the arctangent gives the angle that gives that tangent value.

 Figure 1: Tangent equations.

### References

1. McAdams, David E.. All Math Words Dictionary, tangent. 2nd Classroom edition 20150108-4799968. pg 176. Life is a Story Problem LLC. January 8, 2015. Buy the book
2. Hutton, Charles. A Course in Mathematics, Volume II. 4th edition. pg 2. www.archive.org. G. & J. Robinson. 1804. Last Accessed 12/16/2018. http://www.archive.org/stream/courseofmathemat02huttrich#page/2/mode/1up/search/cosecant. Buy the book

• McAdams, David E.. Cotangent. allmathwords.org. All Math Words Encyclopedia. Life is a Story Problem LLC. 3/12/2009. http://www.allmathwords.org/en/c/cotangent.html.
• McAdams, David E.. Arctangent. allmathwords.org. All Math Words Encyclopedia. Life is a Story Problem, LLC. 12/16/2018. http://www.allmathword.org/en/a/arctangent.html.

McAdams, David E. Tangent. 12/21/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/t/tangent.html.

### Revision History

12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)