10-2

10-2

Formulas:

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

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

Example 1: tan alpha= 2 tan beta= -1/3

First we need to see what formula we’re going to use, the first one tan(a+b). Now you plug into the formula.

2+(-1/3) over 1-(2)(-1/3) = 5/3+(-2/6) over 1-(-2/3) =(4/3) over (5/3), you’re going to sandwich, = 12/13 = 4/5 finally answer J

Example 2: tan75º-tan30º/1+tan75ºtan30º

You’re going to use formula two. tan(a-b)

tan(75º-30º)= tan45º= 1

Example 3: tan100º+tan50º/1-tan100ºtan50º

You’re going to use the first formula.

tan(100º+50º)=tan150, find a reference angle, -tan30º= negative square root of 3 over 3

Example 4: tan alpha= 2/3 tan beta= ½

First you need to figure out what formula you need to use, the first one. tan(a+b). Plug into the formula.

2/3+1/2 over 1-(2/3)(1/2) = 4/6+3/6 over 1-(2/6)= 7/6 over 4/6, sandwich, 42/24 = 7/4 finally answer J

--Danielllllle