Lawrence's blog :p

i will go over section 10 -2 . 10-2 and 10-1 are exactly the same except one involves sin and cos. the other which is 10-2 goes over tan. you have to know these formulas so you can work the problems. if you dont know the formulas you will be lost and wont be able to work the problem. there arent many formulas for these two sections so just know them so you can pass and make b-robs life easier with grading our quizzes and tests.

formulas for 10-2

tan(a+b)= tan(a)+tan(b)/1- tan(a)tan(b)

tan(a-b)= tan(a)-tan(b)/ 1+tan(a)tan(b)

if they give you cot, just flip those two problems and there is your cot. that is really amazing isnt it!


ex. suppose tan(a)=1/3 tan(b)= 1/2. find tan(a+b)

=1/3+1/2
1-1/3(1/2)

= 2/6+3/6
1-1/6

= 5/6
5/6

=1



ex. tan110- tan50
1+tan110 tan50

=tan(110-50)

=tan 60

= square root of 3