Area of a circle

Area of a Circle

  • Definition of Area

    • The area of a circle is defined as the amount of space contained within the boundary of the circle.

  • Formula for Area of a Circle

    • The area can be calculated using the formula:
      ext{Area} = ext{pi} imes ext{radius}^2

    • This formula can also be represented in a more concise form as:
      A = ext{pi} imes r^2
      where:

    • A = Area

    • r = Radius

    • pi (π) is a mathematical constant approximately equal to 3.14.

  • Units of Area

    • The resulting area will be in squared units (e.g., square centimeters, square meters).

  • Example Calculation

    • If the radius of the circle is given as 5 centimeters, we can calculate the area as follows:

    1. Substitute the radius into the formula:
      ext{Area} = ext{pi} imes (5 ext{ cm})^2

    2. Calculate the radius squared:
      5^2 = 25 ext{ cm}^2

    3. Multiply by pi:
      ext{Area} = 3.14 imes 25 ext{ cm}^2

    4. Perform the multiplication:
      ext{Area} = 78.5 ext{ cm}^2

  • Final Result

    • Therefore, the area of the circle with a radius of 5 centimeters is:
      ext{Area} = 78.5 ext{ cm}^2