This investigation describes quantitative relationships between circle segments (portions of a chord, tangent, secant and their co-functions) and the associated intercepted arc. The segments each ...

Click the "Formulas" tab and click "Math & Trig" button in the Function Library group. Scroll down and select "RADIANS" in the list of functions. Type "A2" in the Angle box and click "OK." ...

This article was originally published with the title “A Simple Rule for Certain Trigonometric Identities” in SA Supplements Vol. 75 No. 1950supp (May 1913), p. 315 doi:10.1038 ...

PAUL STEPHENSON, Trigonometric identities from regular polygons, The Mathematical Gazette, Vol. 101, No. 551 (July 2017), pp. 327-334 ...