# function topici don't understand the functions sine and cosine. how it works?

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The sin and cosine functions are trigonometric functions and they are functions of an angle. These functions represent the relations between angles of a triangle and the lengths of the sides of the triangle.

The sine function is definedas the ratio between 2 sides of triangle, namely the opposite side and the hypotenuse, where the hypotenuse is the side opposite to the right angle and the opposite side is opposite to the angle whose sine function we want to find out.

sin A = opposite side/hypotenuse

The cosine function is defined as the ratio between 2 sides of triangle, namely the adjacent side and the hypotenuse, where the hypotenuse is the side opposite to the right angle and the adjacent side is adjacent to the angle whose cosine function we want to find out.

cos A = adjacent side/hypotenuse