Answer:
A trigonometric function that for an acute angle is the ratio between the leg adjacent to the angle when it is considered part of a right triangle and the hypotenuse.
What is cos law?
The cos law or cosine law defines the relationship between the sides and the angles of the triangle. This law is also known as the law of cosine or cosine rule. According to this law,
c2 = a2 + b2 − 2ab cos α
Where a, b and c are the sides of the triangle.