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Circles

Circumference, area and the meaning of π.

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).

Ишлатилган мисол · circle radius 2

Circle radius 2

2

Қадамма-қадам

  1. r = 2

    Everything about a circle follows from its radius.

  2. d = 2r = 4

    Diameter.

  3. C = 2\pi r = 4 \pi \approx 12.566

    Circumference.

  4. A = \pi r^2 = 4 \pi \approx 12.566

    Area.

Жавобни кўрсатиш
C = 4 \pi,\quad A = 4 \pi

Энди сизлар Мавзуни танланг, ёзинг ёки ўзингиз чизинг. Ҳар бир қадам, расм, жавоб сиз сўрагунча яширин.

Ўзингиз ишлашда давом этинг

Бепул ҳисоб ҳар бир дарсга ёзув қўшиб беради, сиз тугатган нарсалар ва ҳал қилинган масалалар бир жойда қайд этилади ва сиз бу саҳифа ҳақида устоздан сўрашингиз мумкин. Математика ўзида очиқ бўлиб, унга кириш ёки киришни истамаган ҳар кимга очиқ.

Ройхатдан ўтиш Кириш

Бу ерда қўлланилган белгилар

Барча белгилар учун тўлиқ таъриф, сурат ва ҳар бир ҳарфнинг маъносини кўриш учун белгини босинг.

Қандай: Circles

  1. Everything about a circle follows from its radius.
  2. Diameter.
  3. Circumference.
  4. Area.

Одамлар сўрайдиган саволлар

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.

Кўпроқ Geometry