Trigonometry For programmers

Question 1

Cosine

Answer 1

Cosine is a fundamental concept in trigonometry used to describe the relationship between the lengths of the sides of a right triangle and its angles. Specifically, the cosine of an angle in a right triangle is the ratio of the length of the adjacent side (the side next to the angle) to the length of the hypotenuse (the longest side of the triangle, opposite the right angle).

Mathematically, it is expressed as:
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Cosine is also an important function in the context of circles and oscillations, defined for all real numbers using the unit circle—a circle with a radius of 1. In the unit circle, the cosine of an angle is the x-coordinate of the point where the terminal side of the angle intersects the circle.

This concept extends beyond geometry and is used in various fields including physics, engineering, and computer science, particularly in analyzing waves, oscillations, and rotations.