Trigonometry is the study of triangles and the
interrelationship of the sides and the angles of a
triangle. In determining ship stability, only that part of
trigonometry pertaining to right triangles is used.
There is a fixed relationship between the angles of a
right triangle and the ratios of the lengths of the sides of
the triangle. These ratios are known as trigonometric
functions and have been given the following names:
sine, cosine, tangent, cotangent, secant, and cosecant.
The three trigonometric functions required for ship
stability work are the sine, cosine, and tangent. Figure
12-1 shows these trigonometric relations.