Final answer:
Trigonometry is a branch of math that studies the relationships between angles and sides of right triangles. Sine, cosine, and tangent functions are used to calculate these relationships. The sine of an angle is equal to the ratio of the opposite side to the hypotenuse, while the cosine is the ratio of the adjacent side to the hypotenuse.
Step-by-step explanation:
Trigonometry is the branch of mathematics that deals with the relationships between angles and the sides of right triangles. Trigonometric functions such as sine, cosine, and tangent are used to calculate these relationships. In a right triangle, the sine of an angle is equal to the ratio of the length of the opposite side to the hypotenuse, while the cosine is equal to the ratio of the length of the adjacent side to the hypotenuse. The tangent is equal to the ratio of the sine to the cosine.