can someone help me to find the sector of a circle ?

2018-05-20 10:20 pm

回答 (7)

2018-05-20 11:16 pm
✔ 最佳答案
Ans:
2018-05-20 10:26 pm
Area of sector
= (Area of circle) × [(Angle at center)/360°]
= π × Radius² × [(Angle at center)/360°]
= π × (6 ft)² × (120/360)
= 12π ft²
≈ 12 × 3.14 ft²
= 37.68 ft²
2018-05-20 10:24 pm
Area of Sector = 120°/360° * area
= 1/3 * pi * 6^2
= 12π ft^2
2018-05-20 10:54 pm
the sector is ⅓ of the circle
area of = ⅓ area of circle = ⅓π6² = 12π ft²
2018-05-21 10:47 pm
In general, a sector of a circle is subtended by a central angle x, say. 3 equal ratios result.
(sector arc)/(circle circumference) = (sector area)/(circle area) = [(x deg./360 deg.) or (x rad/2pi*rad)]. Now in
our problem, circle radius = r, say, = 6 ft. x = 120 deg. Then (120 deg./360 deg.) = (1/3). Now circle circumference = 2pi*r = 2pi*6 ft = 12pi*ft and sector arc = 12pi*ft(1/3) = 4pi*ft. Circle area = pi*r^2 = 36pi*ft^2
Then sector area = (1/3)circle area = (1/3)36pi*ft^2 = 12pi*ft^2.
2018-05-20 10:45 pm
Area of sector = 1/2 r^2θ, where θ is in radians

= 1/2(6)(2π/3)

= 2π ft^2 ............[ = 6.283165307 ft^2]
2018-05-20 10:28 pm
What do you want to know about it?
Area? Since 120° is 1/3 of 360°, the area of the shaded sector is 1/3 the area of the circle; πr²/3 = 12π ft²
Arc Length? Since 120° is 1/3 of 360°, the arc length of the shaded sector is 1/3 the circumference of the circle: 2πr/3 = 4π ft
Perimeter? Perimeter of the shaded sector is the arc length + twice the radius = 4π+12 ft
Something else? You'll have to tell us what you want.


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