Meaning of addition formula in English:
addition formula
noun
MathematicsAn equation in which one quantity is expressed in terms of a sum of other quantities; specifically any of several standard formulae which express a trigonometrical function of a sum or a difference of angles as a sum or difference of products of similar functions of the individual angles.
An example of a trigonometrical addition formula is sin (A + B) = sin A cos B + cos A sin B.
Origin
Late 19th century; earliest use found in Proceedings of the Royal Society of London.
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