Trigonometry gets a lot more fun when we start using cosine. But what exactly is cosine? How do we use it? Let''s find out:
The cosine of an angle is expressed in a trigonometric ratio. This ratio states that:
Cosine = the length of the adjacent side divided by the length of the hypotenuse.
You might recall that the hypotenuse is always the side opposite the right angle. The adjacent angle is neither the hypotenuse nor the opposite side, but rather the side next to the angle.
In other words:
As always, it helps to visualize this concept. Let''s take a look:
In this triangle, the cosine of angle A would be
There are a number of interesting things to keep in mind when dealing with cosine:
Amplitude and Period of Sine and Cosine Functions
Cosine, tangent, and sine are concepts that your student needs to get right the first time around, and a tutor can help them establish confidence in these topics with extra help after class. They can use examples that match your student''s hobbies -- perhaps using sports to explain triangles, for instance. Your student can also receive targeted instruction based on their learning style. Varsity Tutors will match your student with a suitable tutor, so reach out today to get started.