CHAPTER TENNNN

This past week in Advanced Math, we did not get a chance to learn much because it was exam week. We worked on our study guide and reviewed for exams all during the week. On Friday, we started Chapter Ten Section One.

This may sound very scary, but calculators are not allowed.
This is how to find sine and cosine of a number with no calculator.
For cosine
cos(alpha + or - beta) = cos alpha * cos beta - or + sin alpha * sin beta
For sine
sin (alpha + or beta) = sin alpha * cos beta + or - cos * sin beta

In order to survive in this chapter you MUST remember your trig chart. I know, I know, this section just keeps getting scarier.

Here's an example of finding the exact value.

Cos 75
Alpha is 45 and Beta is 30
Then plug it in to the formula.
cos(45 +30)= cos 45 * cos 30 - sin 45 + sin 30
Then simplify
(Square root of 2/ 2) (Square root of 3/ 2) - (square root of 2/ 2) (1/2)
Combine
Square root of 6 over 4 - square root of 2 over 4
So,
Cos 15 = square root 6 - square root of 2 over 4

This section is not very difficult, but it just takes time to memorize and go through all the steps.