Pre-Cal notes
13.1 Triganometric Functions
Gabriel Hansley & Hayden Burkett
Trigonometric Functions in Right Triangles
Words- sin=(sine), csc=(cosecant), cos=(cosine), sec=(secant), tan=(tangent)
cot=(cotangent)
Symbols- sin= opp/hyp csc= hyp/opp cos= adj/hyp
sec= hyp/adj tan= opp/adj cot= adj/opp
Definitions
- Trigonometry- the study of relationships among the angles and sides of a right triangle.
- Trigonometric ratio- compares the side lengths of a right triangle.
- Trigonometric function- a rule given by a trigonometric ratio.
Trigonometric Functions in Right Triangles example #1
sin=(4/5), csc=(5/4), cos=(3/5), sec=(5/3), tan=(4/3)
cot=(3/4)
Trigonometric Functions in Right Triangles example #2
leg opposite: BC=8,leg adjacent: AC=15, hypotenuse: AB=17
sin=(8/17), csc=(17/8), cos=(15/17), sec=(17/15), tan=(8/15)
cot=(15/8)
Trigonometric Values for Special Angles
30-60-90 degree triangles
sin30=(1/2), cos30=(3/2), tan30=(1/3)
sin60=(3/2), cos60=(1/2), tan60=(3)
45-45-90 degree triangles
sin45=(2/1), cos45=(2/1), tan45=(1)