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Theta is used to represent an angle, typically measured in degrees or radians, between two lines or vectors.
An alternative unit for measuring angles based on the radius of a circle. There are 2ฯ radians in a full circle (360 degrees).
Trigonometry: The branch of mathematics that deals with the relationships between the angles and sides of triangles.
A mathematical principle stating that, in a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides.