sine

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noun \ˈsīn\

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 a series of which the first term is θ and succeeding terms alternate in sign with the kth term being a fraction whose numerator consists of θ raised to the exponent 2k - 1 and whose denominator is the factorial of 2k - 1

Origin and Etymology of sine

Medieval Latin sinus, from Latin, curve


First Known Use: 1593


SINE Defined for English Language Learners

sine

play
noun \ˈsīn\

Definition of sine for English Language Learners

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


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