1 Results Area Of A Circle

A circle is the set of all points in a plane at a given distance (called the radius ) from a given point (called the center.)

• Area Of A Circle With Diameter
• Area Of Part Of Circle
• 1 Results Area Of A Circle
• Area Of A Circle Using D

A line segment connecting two points on the circle and going through the center is called a diameter of the circle.

Clearly, if $d$ represents the length of a diameter and $r$ represents the length of a radius, then $d=2r$ .

Area of a Circle with diameter 5.5 meters Disclaimer While every effort is made to ensure the accuracy of the information provided on this website, neither this website nor its authors are responsible for any errors or omissions, or for the results obtained from the use of this information. Right, the area of a unit circle is pi. The sine function does give the height above the horizontal axis of points on the unit circle, but its argument is the angle that the radial line to that point makes with the positive horizontal axis, and so when you integrate sin t with respect to t, you’re not actually computing the area of the unit circle. Explore the formula for the area of a circle, by cutting it into sectors and rearranging the sectors to form a figure close to a parallelogram. Area of a Circle Segment Given the Central Angle Definition: The number of square units it takes to fill a segment of a circle Try this Drag one of the orange dots that define the endpoints of the segment.

The circumference $C$ of a circle is the distance around the outside. For any circle, this length is related to the radius $r$ by the equation

$C=2\pi r$

where $\pi$ (pronounced ' pi ') is an irrational constant approximately equal to $3.14$ .

The area of a circle is given the formula

$A=\pi r^2$ .

Example 1:

What is the area of a circular table with diameter $6$ ft?

Given that, the diameter of the circular table is $6$ ft.

So, the radius of the circular table is half of the diameter. That is, radius is $3$ ft.

Use the formula for area of a circle, $A=\pi r^2$ , where $r$ is the radius of the circle.

Substitute $3$ for $r$ in the formula.

$\begin{array}{l}A=\pi {\left(3\right)}^2\\ =\pi \left(9\right)\\ \approx 28.26\end{array}$

Therefore, the area of the circular table is about $28.26{\text{ft}}^2$

Example 2:

What is the area of the shaded region in the figure shown?

It's clearly marked that the larger circle has a radius $11$ cm. So, its area is

$\begin{array}{l}{A}_{\text{large circle}}=\pi r^2\\ =\pi {\left(11\right)}^2\\ =121\pi \\ \approx 379.94{\text{cm}}^2\end{array}$

What about the smaller circle? Well, the distance from the center to edge is $11$ cm; the diameter of the smaller circle is $11-4=7$ cm. So, the radius of the smaller circle is $3.5$ cm.

$\begin{array}{l}{A}_{\text{small circle}}=\pi r^2\\ =\pi {\left(3.5\right)}^2\\ =12.25\pi \\ \approx 39.47{\text{cm}}^2\end{array}$

To get the area of the shaded region, subtract the area of the smaller circle from the area of the larger circle.

$379.94-38.47=341.47$

Therefore, the area of the shaded region is about $341.47{\text{cm}}^2$ .

In this example, you will learn about C++ program to find area of the circle with and without using the function.

Formula to find area of the circle:

where,

mathematical value of Π is 3.14159.

Let’s calculate the are of the circle using two methods.

Example: C++ program to find area of the circle.

Output

Example: C++ program to find area of the circle using function.

Area Of A Circle With Diameter

Output

Area Of Part Of Circle

Explanation

1 Results Area Of A Circle

In the first program, we have simply calculated area of the circle in the main program.

Area Of A Circle Using D

However, we have used areaOfCircle( ) function for calculating area of the circle in the second program.