Casio fx-570MS - Manual (Page 9)

– 6 –
Circles and Sectors
Example 2 Example 2
Operation
Determine, up to one decimal place, the length of the arc
and area of a sector that has a radius of 6 cm and a
central angle of 240
°.
(Radius = r , central angle = a °)
Length of the arc of a sector: l = 2
π
r
×
Area of a sector: S =
π r 2
×
1 .
Enter the COMP Mode.
F 1
2 .
Press the F key a number of times until degrees (Deg) are specified as the angle unit.
F • • • 1 (Deg)
]
3 .
Press the F key a number of times until 1 (Fix1) is specified as the fixed number of decimal
places.
F • • • 1 (Fix) 1 ]
4 .
Determine the length of the arc of the sector.
2 A x - 6 - R 240 \ 360 T =
The length of the arc of the sector is approximately 25.1 cm.
5 .
Calculate the area.
A x - 6 K - R 240 \ 360 T =
The area is approximately 75.4 cm 2 .
FIX
FIX
Explanation Explanation
a
360
a
360
240
°
6 cm