10-2

In chapter 10-2, we pretty much did the same thing as 10-1 except with different formulas. We still replaced and simplified, just without the sin and cos. You still are not allowed to use calculators for anything in this section either. The formulas you need to remember are:

Tan ( alpha + beta ) = tan alpha + tan beta/1- tan alpha tan beta

Tan ( alpha – beta ) = tan alpha – tan beta/ 1+ tan alpha tan beta

Cot is the opposite (reciprocal) of tan. So, it would be the same formula, just flipped.

Example : simplify
tan 100degrees – tan 10 degrees/ 1+ tan 100 degrees tan 10 degrees

This formula matches with the first one I gave, so you replace the right side with the left side and get: tan ( 100 – 10)

Subtracting is the next step: tan90degrees

Since tan 90 is on your trig chart that is the answer you will get undefined as your answer.