Area of a Circle

It is known that the area enclosed by a circle of radius r is given by πr^2. As you can see here, the Greek letter π represents the constant ratio of a circle's circumference to its diameter, which is approximately 3.14159.

Using the formula A = πr^2, where r is the radius, we can find the area of a circle. An area is measured in square units, such as meters, centimeters, inches, and so on.

Mathematical Form

In a later step, we will use Python to solve the area problem. In order to solve this problem, we will first discuss how it can be expressed mathematically. 

So, we need a radius for our circle that can be any types of unit. A radius is a distance from center to a point on the circle's boundary.  Let the radius (r) is 5. 



So we have this,

        π = 3.14159

        r = 5

Based on this formula A = πr^2, we can calculate the area of a circle.

Putting all values we get,

        A = πr^2

  =>  A = 3.14159 * (5 * 5)

  =>  A = 3.14159 * 25

  =>  A = 78.53982

In other words, the area of a circle is 78.53982.

Now it's time to solve this area problem using Python and it's that simple.

Python Code

Just like above, first we need to accept the radius from a user. After getting the user input we store this input value to a variable called user_radius. But where is pi ?? Don't afread, we need to import the math Library. After importing math library now we can use the pi value.