Tori's.

I am going to go over section 10-2. its almost exact to section 10-1, but this section uses tangent and cotangent.


Formulas:
tan( A+B)= tanA+ tan B/1-tanA tanB
tan( A-B)= tanA- tan B/1+tanA tanB
cot is reciprocal :
cot(A+B)= 1-cotA
cot B/ cot A+ cot B

Examples:

Ex1: suppose tan a= 1/3 tan b=1/2 .
find tan (A+B).
tan A+ tan B/ 1- tan A tan B=
(1/3 + 1/2) /(1-(1/3 )(1/2))=
(2/6 + 3/6)/(1-1/6)=(5/6)/(5/6)=1

Ex2: Simplify tan 110 degrees - tan 50 degrees/ 1+(tan 110 degrees)(tan 50 degrees)=
tan (110-50)=tan 60=
sq. root 3