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If a circle with radius 1 is drawn with the three vertices of the triangle as the center of the circle, the area of the shadow part is more. The shadow is three outer corners
The area of the shadow part can be put together into a semicircle with radius 1, so the area of the shadow part is half π × R2 = half π
As shown in the figure: if the three vertices of a triangle are the centers of three circles with a radius of 3 cm, the area of the shadow part in the figure is () A. π cm2 B. 9 π cm2 C. 4.5 π cm2 D. 3 π cm2
One hundred and eighty
360 × π × 32 = 4.5 π (square centimeter)
A: the area of the sum of the three π. 5cm
Therefore, C
For an arbitrary triangle, draw three small circles with a radius of 2 cm with its three vertices as the center of the circle. What is the sum of the areas of the three shadow parts?
I can't see your picture, but according to your question, I guess your question is: the length of the three sides of the triangle is not less than 4cm, and the three shadow parts are the three fans with the three vertices of the triangle as the center of the circle. The area of the fan is s = π R 2 θ / 2 π, and θ is the central angle of the circle, and the radius of the three sectors is equal, and the sum of the central angles of the circle is π, then s = 2 π
If I get the wrong idea, I hope you can paste it
The area ratio of a square and a circle with equal circumference is () A. π：4 B. 4：π C. 1：1 D. 4：1
Let the circumference of a circle and a square be equal to L,
Then the side length of the square is L
4；
The radius of the circle is L
2π；
So the area of the square is L
4×L
4=1
16L2；
The area of the circle is L
2π）2=L2
4π=1
4πL2；
So 1
16L2：1
4πL2=π：4．
A: their area ratio is π: 4
Therefore, a
The circumference of a circle is equal to that of a square. The circumference of a square is 12.56 decimeters. What is the area of the circle
The circumference of the circle is 12.56 decimeters
Then: 2 × 3.14 × r = 12.56 (R is the radius of the circle)
R=2
Area = 3.14 × 2? = 3.14 × 4 = 12.56 square decimeter
The circumference of a circle and a square are both 12.56 cm. Which area is larger and how much larger?
Circle radius = 12.56 △ 3.14 △ 2 = 2
So the area of the circle is 3.14 × 2? 2 = 12.56 square centimeters
Square side length = 12.56 △ 4 = 3.14 cm
So the square area = 3.14? 2 = 9.8596 square centimeters
So the area of the circle is large, 12.56-9.8596 = 2.7004 square centimeters
The area of a circle and a square is 2 π cm2. Which of them has a larger circumference? What can you learn from it?
(1) If the radius of a circle is RCM, then
πr2=2π，
The solution is r =
Two
The circumference of the circle is 2 π r = 2 π×
2≈8.88；
If the side length of a square is ACM, then
a2=2πa＝
2π≈2.506
Then the circumference of the square is 4A ≈ 10.02 ＞ 8.88
Then the circumference of the square is larger
(2) Enlightenment: when the area of a circle and a square are equal, the circumference of a square is larger
The area of a circle and a square is 2 π cm2. Which of them has the larger circumference? Super urgent!
According to the meaning of the title: the radius of the circle is the root (2) cm, and the side length of the square is the root (2 π) cm
The circumference is 2 π root sign (2), and square circumference is 4 root sign (2 π)
By comparison, the circumference of the square grows up
What is the ratio of the inscribed and circumscribed sides of a square?
Radical 2
If you set the straight D of the circle, then the side length of the inscribed square is 2 / 2 of the root, and the side length of the circumscribed regular six deformation is 1 / 2D!
Is the ratio of the radius of the inscribed circle and the radius of the circumscribed circle of an equilateral triangle 2:1 The radius of the inscribed circle of an equilateral triangle is 3:4:5, right
For Pythagorean theorem, the ratio of radius of inscribed circle and circumscribed circle of equilateral triangle is 2:1
The side length of a square circumscribed by a circle is equal to 2 times the root of its edge center distance
The radius of the inscribed circle of an equilateral triangle is 3:4:5
The radius and height ratio of circumscribed circle is 1:2:3
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