It can be tricky to calculate the cosine of an angle, however, some ways can make the process easier. The easiest way to calculate the cosine of an angle is to find the length of an adjacent side and divide it by the hypotenuse. The technical terms themselves can trip people up sometimes more than the calculating itself.
Adjacent means that a line is next to or connecting to another line. The hypotenuse is the longest side of a right angle. When all of these terms and processes are understood finding the cosine of an angle becomes an easy thing to do.