Definition of sine
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 : 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
Recent Examples of sine from the Web
The link was so clear it could be described in derivative sines and cosines, mathematical concepts taught in college trigonometry.
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Origin and Etymology of sine
Medieval Latin sinus, from Latin, curve
First Known Use: 1593
SINE Defined for English Language Learners
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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