If the area of the sector with a 72 ° central angle is 628 square centimeters, the area of the circle to which the sector is directed is () square centimeter

If the area of the sector with a 72 ° central angle is 628 square centimeters, the area of the circle to which the sector is directed is () square centimeter

628÷72/360
=628÷1/5
=3140 square centimeter
If the area of the sector with a 72 ° central angle is 628 square centimeters, the area of the circle to which the sector is directed is (3140) square centimeters

The area of a sector is 100 square centimeters, and the center angle of the circle is 100 degrees. What is the area of the circle where the fan is located? A 360 × 100 △ 100 square centimeters B100 parts 150 × 100 square centimeter C 360 per 100 square centimeter D 360 x 100 square cm

100÷100×360=360°
A 360 × 100 △ 100 square centimeter should be selected

The radius of a circle is equal to that of a sector. The area of the circle is known to be 30 square centimeters, and the center angle of the sector is 36 degrees

30÷3.14=r2，
36×3.14×(30÷3.14)
360，
=30
10，
=3 (square centimeter);
A: the area of the sector is 3 square centimeters

If the area of the sector with a center angle of 60 ° is 314 square centimeters, then the area of the circle where the fan is located is_______ . Formulas and processes

314 × (360 ° to 60 °) = 1884 square centimeters

If the area of a sector accounts for 1 / 12 of the area of the whole circle, then the degree of the central angle of the sector is -? What's the urgency

1/12×360=30°

Given that the chord length of the central angle of a circle with radian number 2 is also 2, then the arc length of the central angle of the circle is () A. 2 B. 2sin1 C. 2sin-11 D. sin2

As shown in the figure, in the sector OAB, let the center angle ∠ AOB = 2, and make OC ⊥ AB at point C through point 0,
Extend OC and intersect AB at point D,
Then ∠ AOD = ∠ BOD = 1, AC = 1
2AB=1，
In AOC, Ao = AC
sin∠AOC=1
Sin1, r = 1
sin1，
The length of arc AB is L = α· r = 2.1
sin1=2
sin1=2sin-11．
Therefore, C

Given that the chord length of the center angle of 2 radians is 2, then the arc length of the center angle of the circle is () A. 2 B. sin2 C. 2 sin1 D. 2sin1

Connecting the center of a circle and the midpoint of a chord, a right triangle is formed by the distance between chord centers, half of the chord length, and radius. The half chord length is 1, and the center angle of the circle it is facing is also 1
So the radius is 1
sin1
The arc length to which the central angle of the circle corresponds is 2 × 1
sin1=2
sin1
Therefore, C is selected

Given that the chord length of the central angle of a circle with radian number 2 is also 2, then the arc length of the central angle of the circle is () A. 2 B. 2sin1 C. 2sin-11 D. sin2

As shown in the figure, in the sector OAB, let the center angle ∠ AOB = 2, and make OC ⊥ AB at point C through point 0,
Extend OC and intersect AB at point D,
Then ∠ AOD = ∠ BOD = 1, AC = 1
2AB=1，
In AOC, Ao = AC
sin∠AOC=1
Sin1, r = 1
sin1，
The length of arc AB is L = α· r = 2.1
sin1=2
sin1=2sin-11．
Therefore, C

It is known that the arc length to which the central angle of a circle is 1 m and the radius of the circle is 1 m

Arc length formula: l = n π R / 180
So 1 = 1 * π * r / 180
The results show that r = 180 / π ≈ 57.32

Calculation formula of arc radian

α = L / r = 2S / (R ＾ 2) Note: α is radian, l is arc length, R is radius, s is arc area