Kaitlyn's Blog

This week we learned about the Trigonometric Functions, which are:
1. Sine
2. Cosine
3. Tangent
4. Cotangent
5. Secant
6. Cosecant

Sine, in the coordinate plane, is defined as y/r. It is positive in the quadrants where y is the positive. Cosine is defined as x/r. It is positive in the quadrants where x is the positive. To find Sin (theta) and Cos (theta) of a circle in the unit circle, you would take the point given and mark it on the coordinate plane. Then you would connect the points to form a triangle.

Ex: If the terminal ray of an angle in standard position passes through ( -4, 6), find sin(theta) and cos(theta).
-To solve this you must mark the point on the coordinate plane, draw a line from the point going down and another line from the point to the origin. Then find the hypoteneuse (r).
- sin(theta)=y/r cos(theta)=x/r

Tangent: tan(theta)=y/x
Cotangent: cot(theta)=x/y
Secant: sec(theta)=r/x
Cosecant: csc(theta)=r/y

To solve for these equations, you would do the same thing that you did to solve for Sine and Cosine.

I understood this week's lessons pretty well, but sometimes it could get confusing. We also learned about solving reference angles. This will only be complicated for me because of the trig chart. It's a lot to remember. I got confused on how to solve the inverses of the functions without a calculator. I'm still not quite sure how to do it, but i think that i will be able to get the hang of it.