Here are the essential concepts you must grasp in order to answer the question correctly.
Unit Circle
The unit circle is a circle with a radius of one centered at the origin of a coordinate plane. It is fundamental in trigonometry as it provides a geometric interpretation of the sine, cosine, and tangent functions. The coordinates of points on the unit circle correspond to the values of these functions for various angles, allowing for the determination of exact values for trigonometric functions.
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Introduction to the Unit Circle
Angle Measurement and Coterminal Angles
Angles can be measured in degrees or radians, and understanding how to convert between these two systems is crucial. Coterminal angles are angles that share the same terminal side when drawn in standard position, which can be found by adding or subtracting multiples of 360° (or 2π radians). For the angle -1860°, finding a coterminal angle helps simplify the calculation of trigonometric functions.
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Rationalizing Denominators
Rationalizing the denominator is a process used to eliminate any radical expressions from the denominator of a fraction. This is important in trigonometry when dealing with exact values that may involve square roots. By multiplying the numerator and denominator by the appropriate radical, one can express the trigonometric function values in a more standard form, making them easier to interpret and use.
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Rationalizing Denominators