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Inner and outer circle area formula
The formula of area of inner and outer circles is S= side length × side length =(2r)×(2r)=4r?

Lateral area's formula in an excircle, also called the formula of circumscribed rectangular area, refers to the square in a circle, so that all four vertices of the square are on the circle, forming the shape of the inner side of the excircle. The formula for calculating the lateral area in the outer circle is simple. You just need to determine the side length of the square, that is, the diameter of the circle, and then multiply it by itself.

Specifically, if the radius of the excircle is r, the diameter of the excircle is 2r. Because the diameter of the circle is equal to the diagonal length of the square, the side length of the square is 2r. So the area s in the outer circle is S= side length × side length =(2r)×(2r)=4r? .

We can translate the area formula of the inner side of the excircle into mathematical language, which is convenient for us to understand: if D is the diameter of the excircle, then the area of the inner side of the excircle is (D? )/2。

In a word, the formula of inner area of outer circle is a basic geometric concept, which can help us calculate the area of a square in a circle. In practical application, this formula is often used in architecture, design, engineering and other fields, such as railway, highway or bridge construction. When we need to build some facilities within a certain space limit, we need to use the area formula in the outer circle to calculate the appropriate size.

How to calculate the area outside the inner circle?

The area outside the inner circle can be calculated by the following formula: area = area of square-area of circle.

Among them, the area of a square can be calculated by the square of the side length, and the area of a circle can be calculated by multiplying the square of the radius by t.

Application of formula of inner circle and outer area

The formula of inner and outer circle area is widely used in various mathematical and engineering problems. For example, it can be used for the layout of computer chips or for analyzing the storage capacity of cylindrical structures such as pipelines and oil tanks.

Practical calculation of formula for outer area of inner circle

The following is an actual calculation example of the formula for the outer area of the inner circle:

If the diameter of the inner circle is 10 cm, then the radius is 5 cm. According to the formula, the area of the inner circle is:

Area of circle = square of radius x3. 14.