What is the formula of the outer circle and the inner circle?
The formula for calculating the outer inner circle is: area = (4-π) r * r = (1-π/4) a * a.
The formula for calculating the inside of the outer circle is: area = (π-2) r * r = (π/2-1) a * a.
On the same plane, the set of points whose distance to a fixed point is equal to a fixed length is called a circle. A circle can be expressed as a set {m |||| mo | = r}, and the standard equation of a circle is (x-a)? + (y - b)？ = r？ . Where o is the center of the circle and r is the radius.
A circle is a conic curve, which is obtained by cutting a cone from a plane parallel to the bottom of the cone.
Extended data:
The arc is generally represented by three letters, and the lower arc is generally represented by two letters. The optimal arc is an arc with a central angle greater than 180 degrees, and the suboptimal arc is an arc with a central angle less than 180 degrees.
In the same circle or in the same circle, if the distance between two central angles, two peripheral angles, two sets of arcs, two chords and one of the two chords is equal, the corresponding other groups are equal.
In the same circle or in the same circle, the circumferential angle of an equal arc is equal to half of the central angle it faces (the circumferential angle and the central angle are on the same side of the chord). The circumferential angle of the diameter is a right angle. The chord subtended by a 90-degree circle angle is the diameter.
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