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
Famous quotes containing the words angle, sum and/or difference:
“Modesty is the only sure bait when you angle for praise.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
“Genius is no more than childhood recaptured at will, childhood equipped now with man’s physical means to express itself, and with the analytical mind that enables it to bring order into the sum of experience, involuntarily amassed.”
—Charles Baudelaire (1821–1867)
“I have always suspected that too much knowledge is a dangerous thing. It is a boon to people who don’t have deep feelings; their pleasure comes from what they know about things, and their pride from showing off what they know. But this only emphasizes the difference between the artist and the scholar.”
—Margaret Anderson (1886–1973)