Diameter is the piece which is connecting two points of a circle and passing through its center. Also diameter call length of this piece. Let's consider several ways of calculation of diameter of a circle depending on basic data.
Instruction
1. Diameter (D) in size is equal to two radiuses (R) :D = 2*R
2. If length of a circle (L) is known, then: L = 2*Pi*RD = L / Pi
3. If the area of a circle (S) is known, then: S = Пи*R^2D = 2*v (S/Pi)
4. In the Cartesian to system coordinates: the general equation of a circle with the center at the beginning of coordinates: x^2 + y^2 = R^2, otsyudad = 2*v(x^2+y^2) if are known coordinates of both ends of diameter (x1, y1) and (x2, y2) :D = v ((x1-x2) ^2+(y1-y2) ^2)
5. In a case with a circumscribed about a triangle circle: a/sin (alpha) = b/sin (beta) = with / sin (scale) = 2R = D where a, b, c are the parties of a triangle, and an alpha, a beta and scale – opposite to them corners.
6. Formulas for radiuses of entered (r) and described (R) of circles of a triangle: R = a*b*c / (4*S) r = 2*S / (a + b + c) where a, b, c are the parties of a triangle, S is its area.