Chapter 10!!!

Sooooo, since we haven't learned any new stuff over the past couple of days, i decided we should go back to the first section of chapter 10 to review. The first thing we're gonna review is the formulas! do you remember them? You should! because we just took a test with them!!!

Sooo, here they areee.

1. cos(alpha+/-beta)=cos alpha cos beta-/+sin alpha sin beta

2. sin (alpha+/-beta)=sin alpha cos beta+/-cos alpha sin beta

3. sin x+sin y=2sinx+y/2 cos x-y/2

4. sin x-sin y=2cosx+y/c sin x-y/2

5. cos x+cos y=2cosx+y/2cosx-y/2

6. cos x-cos y=-2sinx+y/2 sin x-y/2

NOW WHAT DO YOU THINK WE'RE GOING TO DO NEXT?!?!?!?!?!?

Yep! You guessed it! We're going to do an example!!!!!

(REMEMBER: in this chapter you REPLACE, NOT PLUG IN!)

Find the exact value of Sin 15
1. Since sin 15 isn't on the trig chart, you must use a formula that will make it.
2. So you will use Sin(45-30)
3. You will now get, Sin45 cos 30-cos 45 sin30
4. Using the trig chart, you get Sqrt 2/2 x sqrt 3/2 - Sqrt 2/2 x sin 1/2
5. Simplify. You get (sqrt 6-sqrt 2)/4

and there's your review for CHAPTER 10 SECTION 1!!!!!!

CAARRRLLLLEEEEEYYYYYY :)