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A sector with a circumference of 12.56 cm, a radius of 2 cm and a central angle of 90 ° has an arc length of ()
12.56×(90/360)
=12.56×1/4
=14 cm
In the same circle, the ratio of radius to circumference is (), the ratio of diameter to radius is (), the ratio of circumference to diameter is (), and the ratio is ()
Formula: C = π d = 2 π R
Ratio of radius to perimeter: R ratio C = 1:2 π
Ratio of diameter to radius: D ratio r = 2:1
The ratio of circumference to diameter: C ratio D = π ratio 1, the ratio is π
Just use the formula flexibly
The ratio of radius to diameter of a circle is () and the ratio of circumference to radius is ()
The ratio of radius to diameter of a circle is (1:2), and the ratio of circumference to radius is (6.28:1)
In the same circle, the ratio of circumference to radius is___ The ratio of diameter to radius is___ .
（1）C：r=2πr：r=2π：1；
（2）d÷r=2；
So the answer is: 2 π: 1, 2
In the same circle, the simplest integer ratio of radius to diameter is () and the ratio of circumference to diameter is () In the same circle, the simplest integer ratio of radius to diameter is () and the ratio of circumference to diameter is () For a right triangle, the degree ratio of two acute angles is 2:1, and the two acute angles are () degree and () degree respectively Two thirds of a pack of sugar is 80kg, and 1 / 4 of it is 〔 kg 〕
In the same circle, the simplest integer ratio of radius to diameter is (1:2), and the ratio of circumference to diameter is (π: 1)
For a right triangle, the degree ratio of two acute angles is 2:1, and the two acute angles are (60) degrees and (30) degrees respectively
Two thirds of a pack of white sugar is 80 kg, and 1 / 4 of it is 30 kg
Ask me what you don't understand,
No matter how big a circle is, the ratio of its circumference to its diameter is a constant value
C (perimeter) / D (radius) = 3.14
Yes
In the same circle, the ratio of radius to diameter is () and the ratio of circumference to diameter is ()
In the same circle, the ratio of radius to diameter is (1:2), and the ratio of circumference to diameter is (3.14:1)
In the same circle, the ratio of circumference to radius is___ The ratio of diameter to radius is___ .
（1）C：r=2πr：r=2π：1；
（2）d÷r=2；
So the answer is: 2 π: 1, 2
If the length of an arc with a radius of 6cm is equal to the circumference of a circle with a radius of 1cm, then the circular angle of the arc is opposite
60 degrees
The circumference of a circle with a radius of 1cm = 2x pails and XR = 2 pails
The circumference of a circle with a radius of 6cm = 12 pails
2 schools / 12 schools x 360 = 60 degrees
It is proved that in the same circle, the circle angles of the same chord are complementary Why the other diagonal
The two corners and four sides corresponding to a chord form a quadrilateral. The chord is a diagonal line of the quadrilateral, and the other diagonal is a diameter. The circumference angle corresponding to the diameter is a right angle. Then the two corners at both ends of the string are right angles. The sum of the two circumference angles corresponding to the remaining chord is 360-90-90, which is 180 degrees. Therefore, these two angles complement each other
In addition, the circular angles of the same side of the chord are equal everywhere, so we can analyze the case of two isosceles triangles
RELATED INFORMATIONS
- 1. Relationship between circle angle and circle center angle There is a chord in a circle with radius 1. If its length is root 3, then the degree of the circle angle to which the chord is opposite is equal to ()
- 2. The radius of the inscribed circle of the square is R. find the radius of the circumscribed circle of the regular hexagon and its side length I've never learned a function to find the radius of the circumscribed circle and the length of its side. ... without functions
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- 4. It is known that the area of a circle is 6.28 square meters, and the radius of the circle is equal to the side length of the square
- 5. The side length of the two squares in the figure is 10 cm and 6 cm respectively
- 6. Square, circle, rectangle, trapezoid, triangle, parallelogram, cone, cylinder surface area and volume, area, perimeter is what calculation formula!
- 7. A square and a circle have the same radius. The area of the circle is 28.26 square centimeters. What is the area of the square
- 8. Use six squares of the same size to make the following figure. The shadow area is 12 square centimeters. Can you figure out the area of the blank part?
- 9. The circle O of the equilateral triangle ABC with circumference of 6 π and radius of 1 starts from the position where AB is tangent to point D Then: on the outside of triangle ABC, roll clockwise along the triangle and return to the position of point d tangent to ab. how many cycles does circle O rotate? What do you mean by turning the outer angles of three triangles? Why can you turn one angle by turning an outer angle? Why not turn 240? You'd better take the picture to solve it! How to turn it?
- 10. In the equal ratio sequence an, TN is the product of the first n terms. If TN = 1, then A .a2=1 B.a3=1 C.a5=1 D.a9=1
- 11. If the length of an arc is 1 / 4 of the circumference of the circle, the angle of the center of the arc is ()
- 12. If a circle is divided into four sectors a, B, C and D, and the area ratio of sector ABCD is 2:1:4:5, what degree is the center angle of the largest sector
- 13. If the circumference of a sector with radius 2 is equal to the arc length of its semicircle, then the central angle of the sector is___ Radian, the sector area is___ .
- 14. In the circle center o with radius of 50 mm, chord AB is 50 mm long. Calculate the degree of angle AOB and calculate the distance from point O to ab by using the vertical diameter theorem
- 15. The ratio of the length of the two arcs divided by the chord is 2:7, and the degree of the circumferential angle of the chord is______ .
- 16. There is a chord in a circle with radius 1. If its length is root 3, then what is the degree of circumference angle of this string Can we do it without trigonometric functions?
- 17. What is the equation for all lines passing through the point (- 3,1) and the line farthest from the origin
- 18. The linear equation passing through point a (1,2) and the maximum distance from the origin is______ .
- 19. Given that the straight line L passes through the point (- 2,3) and the distance from the origin to the line L is 2, then the equation of the line L is______ .
- 20. Find the equation of the line with root sign 10 which is perpendicular to the straight line x + 3Y + 5 = 0 and the distance from the point P (- 1.0) is three fifths times