Circular measure.ppt

nota

1. Circular measure
Chapter 8

2. OBJECTIVE
•Understand the concept of radian
•Determine
a)Length of arc
b)Radius
c)Angle subtended at the center of a circle
based on given information
d)Find perimeter of segment of circle
e)Area of sector and segment

3. Concept Map
Circular measures
Arc length,s
s= rѲ
Πrad= 180⁰
x 180⁰/ π
X π/180⁰
degree radian
Area of segment AB
= Sector of AOB –
Area of ∆ OAB
= ½ r²Ѳ-½ r² sinѲ
= ½ r²(Ѳ-sinѲ)
Area of sector A
A= ½ r² Ѳ

4. Convert measurements in radian to
degrees and vice versa
•Convert angle in degreesto radian( in term of π)
a.30⁰ =
b.270 ⁰ =
•Convert angle in radianto degrees( in term of
degree and minute)
a.⅗ πrad=
b.0.215 rad=

5. Calculate length of arc(s)
a)
b)

6. Find the area of sector( shaded area)
a)
b)

7. Find the area of segment (shaded area)
1.64 rad
1,98 rad
a) b)