Law of Sines
Let 
, 
, and 
be the lengths
of the legs of a triangle opposite
angles 
, 
, and 
. Then the law of
sines states that
 |
(1)
|
where 
is the radius of the circumcircle.
Other related results include the identities
 |
(2)
|
 |
(3)
|
the law of cosines
 |
(4)
|
and the law of tangents
![(a+b)/(a-b)=(tan[1/2(A+B)])/(tan[1/2(A-B)]).](/images/equations/LawofSines/NumberedEquation5.gif) |
(5)
|
The law of sines for oblique spherical triangles states that
 |
(6)
|
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