1. Trigonometric Formulas
Honors Precalculus
April 18, 2018
Mr. Agnew

2. Essential Stuff Essential Question Essential Vocabulary
How do you find the lengths of arcs and areas of sectors?
Essential Vocabulary
Intercepted Arc
Sector
Radian Measure

3. Heron’s Formula
If three sides of a triangle are known, we can use Heron’s Formula to find the area of that triangle:
s = ½ (a + b + c)
Examples

4. Lengths of Arcs Length of an intercepted circular arc: s = r θ
s = length of arc
r = radius
θ = angle measure (in radians)

5. Area of a Sector A = ½ r2 θ Area of a sector of a circle:
A = area of sector
r = radius
θ = angle measure (in radians)
Examples: pg # (O), 57 – 61 (O)

6. Homework: 4/18/18
page 541 #33, 35, 37, 38, 41, 42 page 365 #75, 77, 85, 89, 95, 116