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A Derivation of the Formulas for$\sin (\alpha + \beta)$and$\cos (\alpha + \beta)$
A. K. BettingerVolume:
60
Language:
english
Journal:
The American Mathematical Monthly
DOI:
10.2307/2308264
Date:
February, 1953
File:
PDF, 296 KB
english, 1953