Angle Sum and Difference Identities
See also: #Product-to-sum and sum-to-product identitiesThese are also known as the addition and subtraction theorems or formulæ. They were originally established by the 10th century Persian mathematician Abū al-Wafā' Būzjānī. One method of proving these identities is to apply Euler's formula. The use of the symbols and is described in the article plus-minus sign.
| Sine | |
|---|---|
| Cosine | |
| Tangent | |
| Arcsine | |
| Arccosine | |
| Arctangent |
Read more about this topic: List Of Trigonometric Identities
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