lawrence's blog :.(

last week was pretty rough for me. I had alot of tests and on top of that i was worrying about our adv. test. i was doing anything and everything i could do to know the formulas by heart. the first test i failed, but i know the second test i passed. hopefully chapter 11 will be easy but i doubt it. nothing in adv. ath can be easy for us.

i will go over chapter 10 section 1 again because that eas the easiest part and i wish every section was like this one.

formulas:

cos(alpha +/- beta) cos alpha cos beta -/+ sin alpha sin beta
sin(alpha +/- beta) sin alpha cos beta +/- cos alpha sin beta

alpha and beta come from the trig chart and add or subtract to get the abgle you are looking for.

ex.1 find the exact value od sin 15
alpha= 45
beta=30

sin(45-30) you plug those into you formula then you should get

square root2/2( square root3/20)- square root2/2(1/2)

square root6/4- square root2/4
=square root6- square root2/ 4