Inverse Trig Functions Law of the Sines Notation Inverse Trig Functions, Law of the Sines & Requirements Practice Problems

Notation  New variables for angles  Alpha  Beta  Gamma  Theta 2

Inverse Trig Functions  Arcsine  sin -1  Arc-cosine  cos -1  Arctangent  tan -1 3

Inverse Trig Functions(Cont.)  Reverse the trig function process, where: the arc functions provide for: 4

Inverse Trig Functions Example  Solve to the nearest degree: 5

Area of a Triangle 6

Area of a Triangle Example  Find the area of the triangle given B=85˚, c=23 ft., and a=50 ft. to the nearest tenth. 7

Law of the Sines 8

 Requirements  Two sides and an angle opposite to one of them SSA  Two angles and any side AAS or ASA  If these conditions are not met, the problem cannot be solved with the Law of the Sines 9

Example 10

Example (Cont.) 11

Tips  Check your calculator settings  Make sure you are in degree mode when working with degrees and in radian mode when working with radians!!!!  Remember the sum of all angles in a triangle is 180 degrees or pi radians  Not all problems can be solved with the Law of Sines 12