What is a radius? Radius of a circle
What is a radius? The geometry of a circle What is a radius? The radius of a circle is the distance from the center point to the edge of the circle. It's the same [...]
What is a radius? The geometry of a circle What is a radius? The radius of a circle is the distance from the center point to the edge of the circle. It's the same [...]
What is pi? The geometry of a circle What is pi? Pi is a number that is just a little bigger than 3.14. It is the number you get if you divide [...]
Proof for the area of a circle: Divide a circle up into sections like an orange Euclid's proof We know it's true that A=πr-squared is the area of a circle, but how can we prove [...]
Area of an oval The area of an oval is the part of a plane that is inside its circumference. To figure out the area, you need to measure the height and width of the oval. [...]
The geometry of a circle The area of a circle is the flat surface inside its circumference. The area is always equal to the radius squared, multiplied by π (pi). Here's a proof that [...]
Greek mathematics: An Egyptian papyrus from about 100 AD which is a piece of one of Euclid's books Greek math: geometry not algebra Because people in ancient Greece had only very clumsy [...]
Chinese numbers: number rods Chinese numbers People in China were using written numbers by about 1500 BC, in the Shang Dynasty. This is about two thousand years later than people began [...]