π is the ratio of any circle's circumference to its diameter, the same number for a coin and for a planet. From the radius alone you get the diameter (2r), the circumference (2πr) and the area (πr²).
Pracovný príklad · circle radius 2
Teraz ty Vyberte si problém, alebo napíšte alebo nakreslite vlastný.Každý krok, obrázok, odpoveď skrytá, kým sa neopýtate.
Bezplatný účet pridáva poznámky ku každej lekcii, záznam o tom, čo ste dokončili, vaše vyriešené problémy na jednom mieste, a učiteľa, ktorého sa môžete opýtať na túto stránku.Math samotná je otvorená pre každého, prihlásený alebo nie.
Zaregistrovať sa PrihlásenieSymboly použité tu
Ťuknutím na ľubovoľný symbol zobrazíte úplnú definíciu, obrázok a význam každého písmena.
Ako nakupovať: Circles
- Everything about a circle follows from its radius.
- Diameter.
- Circumference.
- Area.
Otázky, ktoré ľudia kladú
Why does every triangle have angles adding to 180°?
Draw a line through one vertex parallel to the opposite side: the two alternate angles equal the other two angles of the triangle, and the three angles at the vertex lie on a straight line. That is Euclid's proof, and it is why the fact holds only on a flat plane.
When do I use the law of sines versus the law of cosines?
Cosines when you know three sides, or two sides and the angle between them. Sines when you know an angle and the side opposite it, plus one more piece.
What is the difference between area and perimeter?
Perimeter is the length of the boundary (one dimension, measured in metres); area is the amount of surface inside (two dimensions, square metres). Doubling every side doubles the perimeter but quadruples the area.
Viac v kategórii Geometry
TrianglesPythagorean theoremPolygonsSolidsCoordinate geometryEuclid's axioms and the structure of proofCongruent and similar trianglesCircle theoremsTransformations: translation, rotation, reflection, dilationSolid geometry: prisms, pyramids, spheres