Precalc 6.2 Notes.notebook
Precalculus Sec. 6.2
Law of Cosines
A
c
b
B
a
­ there are three formulas, but you only use one depending on the given information.
C
­ Law of Cosines is the most algebra intense to solve compared to any other way we have talked about so far, so always look for the easier ways to solve if it is possible.
­ Always find the largest angle first.
Precalc 6.2 Notes.notebook
Example
9
A
Solve the triangle.
C
a
B
12
Precalc 6.2 Notes.notebook
Example
Solve the triangle.
19
8
14
Precalc 6.2 Notes.notebook
Heron's Area Formula
Given any triangle with sides of lengths a, b, and c, the area of the triangle can be found by
where
Precalc 6.2 Notes.notebook
Precalc 6.2 Notes.notebook