Trigonometry of a Right Triangle Geometry Mr. Belanger
Parts of a Right Triangle Theta (angle measure) Opposite Adjacent Hypotenuse Always longest side (opposite from right angle) All the way on other side of triangle Leg next to reference angle
Parts of a Right Triangle A B C 40 What side is adjacent, opposite and hypotenuse for given theta?
SIN SIN ( )=
COS COS ( ) =
TAN TAN ( ) =
Matching Sides SIN= COS = TAN =
Mnemonic Device S O H C A H T O A ININ PPOSITEPPOSITE YPOTENUSEYPOTENUSE OSOS DJACENTDJACENT YPOTENUSEYPOTENUSE ANAN PPOSITEPPOSITE DJACENTDJACENT
Examples: FIND X SIN (45) = X/ SIN (45) = X miles = X
Examples: 56 How far is ladder from wall? P Another Way??? Or find other angle and use another relationship.
Examples: Find COS ( ) = 8/10 Use COS -1 (8/10) = 36.9