arc sine

mathematics

Also known as: inverse sine, sin-1

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June 18, 2026

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The arcsine, abbreviated as arcsin, is a mathematical function that is the inverse of the sine function. If y is the sine of an angle (\theta), then (\theta) is the arcsine of y. This concept is fundamental in trigonometry and calculus, allowing for the determination of an angle when its sine value is known. The term "arcsine" itself refers to the arc whose sine is a given number.1

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trigonometry
Analytic trigonometry
…the sine function is written arcsin or sin⁻¹, thus sin⁻¹(sin x) = sin (sin⁻¹ x) = x. The other trigonometric inverse functions are defined similarly.
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…the sine function is written arcsin or sin⁻¹, thus sin⁻¹(sin x) = sin (sin⁻¹ x) = x. The other trigonometric inverse functions are defined similarly.
Read More