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sine

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noun \ˈsīn\

Simple Definition of sine

  • geometry : the ratio between the long side (called the hypotenuse) and side that is opposite to an acute angle in a right triangle

Full Definition of sine

  1. 1 :  the trigonometric function that for an acute angle is the ratio between the leg opposite the angle when it is considered part of a right triangle and the hypotenuse

  2. 2 :  a trigonometric function sin θ that for all real numbers θ is exactly equal to the sine of an angle of measure θ in radians and that is given by the sum of the alternating series

Origin of sine

Medieval Latin sinus, from Latin, curve


First Known Use: 1593


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