The equation \textcsc(\theta) = \frac1\sin(\theta) defines the cosecant function in trigonometry. Here, \textcsc(\theta) is the cosecant of an angle \theta , which is the reciprocal of the sine function, \sin(\theta) . This means that if you know the sine of an angle, you can find the cosecant by taking the inverse of that value. Cosecant is one of the six fundamental trigonometric functions, which also include \sin(\theta) , \cos(\theta) , \tan(\theta) , \sec(\theta) , and \cot(\theta) . These functions are essential in various fields, including mathematics, physics, and engineering, as they help describe relationships in right triangles and periodic phenomena.