10-2

This week we completed the nine week grading period and worked on chapter ten; Trigonometric Addition Formulas. Many things from chapters 7-9 (which we learned in the first nine weeks) are helpful and very useful in chapter ten such as: the Trig Chart, converting radians to degree and vice versa, and of course the identities. Like in section 10-1, no calculators are to be used in neither 10-3 nor 10-4. Section 10-2 is pretty much the same as 10-1, but a different formula is used for tangent.

The formula for tangent is as follows:
*imagine a as alpha, and b as beta ;)
Tan(a+b) = tan a+ tan b/1-(tan a)(tan b)
Tan (a-b) is the reciprocal
Tan (a-b) = tan a-tanb/ 1+(tan a)(tan b)


Example:
Find tan(a+b) when a=30 b=15
Tan(a+b)=tan(30+15)
=Tan(45)
Tan(45) is on the trig chart, yay!
Because tan 45 is one, the answer is one.
=1
And that’s all there is to it:)