Special Right Triangles

Hey everyone, This is Alex here and I'll be scribing for yesterdays class. I apologize for the late scribe I seemed to be having some technical difficulties with the blog. But anyways here goes,
Yesterday we covered the topic of Special right Triangles and below is some info on them.

Special Angles: Most angles on the unit circle on based on reference angles of either 30°, 45°, or 60°.

Below is an Example of an Isosceles right triangle and how to solve for the missing hypotenuse which will aid us in find the value of SinΘ, CosΘ, and Tan Θ.



As you can see, by using the Pythagorean Theorem you can calculate the missing hypotenuse and use in calculating SinΘ for other given angles.

We can also use this method in solving for angles in a 30° and 60° Triangle.

Once we know the Sin, Cos and Tan values of 30°, 45°, 60°, and 90° we then already know the values of all the other Reference Angles. These Values are basically the same, we must however remember the C.A.S.T rule in order to determine whether or not the value of Sin, Cos, or Tan is negative or positive.

Below is a diagram of the C.A.S.T rule and an example of how it is used.

The C.A.S.T rule tells us which values are positive in the unit circle. For example if a 45° triangle
was located in Point A of the unit circle then all the values of Sin, Cos, and Tan would be Positive.

Alright then now that we this we can solve the missing values in the Tables of our Trig booklets, and seeing as we've already done then congratulations, you now know how to solve the Sin, Cos and tan values of the unit circle :)

Hope you enjoyed my scribe, bye everyone.