Given that the radius of the sector is 3cm and the arc length is 25.12cm, the area of the sector can be calculated

Given that the radius of the sector is 3cm and the arc length is 25.12cm, the area of the sector can be calculated

Given that the radius of the sector is r = 3cm and the arc length is C = 25.12cm, the area of the sector s?
If the radius is r = 3cm, the circumference = 2 * π * r = 2 * π * 3 = 18.85cm, the arc length should be less than the circumference!

Know the arc length (12cm) and area (8cm2) of the sector, how to find the radius of the circle?

We know that there is only one arc length (12cm) and area (8cm2) of a sector. If it is perimeter and area, there are only two
If the perimeter L and the area s are known
Let R be the radius, then l-2r is the arc length
S=1/2*r*（L-2r）
There are two solutions to this equation

If the chord of a circle intersects with its diameter at an angle of 30 degrees and is divided into two parts of 8cm and 2cm in diameter, then the chord center distance is______ cm．

According to the meaning of the title, draw the corresponding figure, as shown in the figure: from the meaning of the title, am = 8cm, BM = 2cm, ∧ AB = am + BM = 10cm, ∧ ob = 5cm, that is om + MB = 5cm, ∧ om = 502 = 3cm, O as OE ⊥ CD, CD at point E, in RT △ ome, OM = 3cm, ∧ ome = 30 ° and ∧ OE = 12om = 1.5cm

Is the center angle, the arc and the chord of the same chord equal?

In the same circle or equal circle, the center angle, arc and chord are equal

In the same circle or equal circle, the following four propositions are known: (1) the arcs opposite the unequal central angles of the circles are not equal; (2) the distance between the centers of the chords of the longer chords is shorter; (3) the chords opposite the equal arcs are equal; (4) if the arcs are expanded twice, the chords opposite will be expanded twice. In fact, the number of correct propositions is

The correct ones are: (1), (2), (3), a total of 3;
I'm glad to solve the above problems for you. I hope it will be helpful to your study

In an equal circle, the center angles of equal arcs are equal. Which chord is equal?

All right = =, or the topic is wrong, the chord of equal arc pair is affirmative, and the center angle of equal circle is equal = =, which are theorems

In the same circle, the equal chord is equal to the equal arc. In the same circle, the arc opposite to the equal center angle is equal
That's right?

In the same circle, equal chord equals arc pair
In the same circle, the arcs of equal center angles are equal pairs
All right!

In the same circle or equal circle, the arcs and chords of equal central angles are equal. Can we remove them from the same circle or equal circle? Why

No
In the same circle or equal circle, = = = is the precondition of the conclusion
Equal central angles of circles are equal to arcs and equal to chords. This is the conclusion

In a circle O with a radius of 5cm, there is a chord AB, and the central angle of the chord is 90 degrees. What is ab equal to

5√2.
Connecting the center of a circle with a and B, it can be proved that the enclosed triangle is isosceles right triangle

When the chord AB = 8, the chord center distance is 4 times the root sign 3, then the circle center angle AOB=

Chord center distance: = 4 √ 3 half chord = 4 Pythagorean = > radius = 8 = > angle ABO = 60 degrees = > semicircle center angle 30 degrees = > angle AOB = 60 degrees