✉️ Why is the area of a circle π·r² (pi r squared)?

The area of a circle vs a square

$$A=\pi r^2$$

The above is perhaps the best known formula and is also rarely understood. Although the formula for the area of ​​a circle was already known in Ancient Greece, its justification is not easy at all. So it’s a great topic to enrich the “Why?” series.

⭐️ The area of a circle – formula

The area of a circle vs a square

As you can see above – a square and a circle of the same area are not “somehow intuitively easy” related. Moreover, it has even been shown that squaring a circle (a procedure performed using a compass and a ruler without a scale) is impossible! And here comes the brilliant idea with a rectangle. Before I tell you what it is, let’s take a look at what the π·r² formula really says.

The area of a circle - 3+ squares

So there are slightly more than 3 squares of the side r in the circle with radius r.

⭐️ The area of a circle – proof by animation

The area of a circle - proof by animation

I worked hard on this animation, I hope you like it. Let me know in the comments 🙂

Continue reading “✉️ Why is the area of a circle π·r² (pi r squared)?”

✉️ Math is fun – Devil vs Evil – what was the first?

Scalar Calculator - Devil vs Evil - What was first?

A small puzzle – the picture presents a mathematical reasoning on the question “What was first – Devil vs Evil?”. Write in the comment an explanation (short) with the answer. The first 10 correct replies will be rewarded with a promotional code enabling the free installation of the Scalar Pro application.

Continue reading “✉️ Math is fun – Devil vs Evil – what was the first?”

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close