A beautiful proof of why slicing a cone gives an ellipse.

What do Euclid, 12-year-old Einstein, and American President James Garfield have in common? They all came up with elegant proofs for the famous Pythagorean theorem, one of the most fundamental rules of geometry and the basis for...

After many adventures in Wonderland, Alice has once again found herself in the court of the temperamental Queen of Hearts. She's about to pass through the garden undetected, when she overhears the king and queen arguing that 64 is the...

On October 1, 1957, thalidomide was introduced as a new morning sickness cure. Everything seemed great until later the next year, when thousands of infants were born with severe birth defects.

In this video Paul Andersen explains how resistors and capacitors affect circuits. The resistance of a resistor is affected by the resistivity of the material and the geometry of the resistor. The current through a resistor can be...

A shooting star crashes onto Earth and a hideous blob emerges. It creeps and leaps, it glides and slides. It's also unstoppable: no matter what you throw at it, it just re-grows and continues its rampage. The only way to save the planet...

Lots of people believe the Universe is infinite, but there's a good possibility that might not be the case. Which means that there would be an actual edge of the Universe. What happens at that edge? Is there a restaurant?

You'd have a hard time finding the medieval city K_nigsberg on any modern maps, but one particular quirk in its geography has made it one of the most famous cities in mathematics. Dan Van der Vieren explains how grappling with...

Physicists, air traffic controllers, and video game creators all have at least one thing in common: vectors. But what exactly are they, and why do they matter? David Huynh explains how vectors are a prime example of the elegance, beauty,...

Euclid, known as the "Father of Geometry," developed several of modern geometry's most enduring theorems--but what can we make of his mysterious fifth postulate, the parallel postulate? Jeff Dekofsky shows us how mathematical minds have...

Stories of discovery and invention often begin with a problem that needs solving. Summoned by the king to investigate a suspicious goldsmith, the early Greek mathematician Archimedes stumbles on the principle that would make him famous.

New ReviewIn this Grade 7 math lesson, students will learn how to determine the distance between the center of a circle and a point drawn on the circle when the radius is given. We begin by reviewing the definition of a circle’s radius and...

In this shorts video we will find an unknown side length. We are given a pair of triangles and told they are similar figures. Using the definition of similar figures, similar figures have corresponding sides that are proportional, we...

In this shorts video we will rotate a segment 180 degrees. Will will understand that a rotation of 180 degrees is two 90 degree turns. We will rotate about a point or vertex, so, this will be the center of rotation. We will graph the...

In this shorts video we will learn how to find the volume of a cone. We will begin by writing the formula. We will identify the missing variables or dimensions of the cone. Using the provided image we will identify the diameter and...

In this shorts video we will identify the equation of a perpendicular line. We are given a linear equation written in slope-intercept form. We are also given four answer choices in slope-intercept form. Each of the answer choices has...

In this shorts math video we will answer a standardized math test question where we find the volume of a cylinder using diameter. We will review the Volume formula of a cylinder, V=pi times r square times h. We will review the...

In this shorts math video we will answer a standardized math test question where we find the volume of a cone. We are given the measurements of the radius and the height of the cone. We will review the formula for finding the volume of...

In this shorts video we will answer a standardized math test question by finding the volume of a pyramid. We will review the volume formula for a pyramid and learn how to use it. We will understand that B represents the area of the...

In this shorts math video we will learn how to find midpoint of a segment without using the formula to answer a standardized math test question. If you understand the concept of midpoint, there is a shortcut to finding the midpoint of...

In this shorts math video we will find the side of a square using area. We are given the area of a square and asked to find the side length of the square. We will review and use the formula A=s^2, (A equals s squared.) We will rewrite...

In this shorts video we will find the radius of a cylinder using volume. We will answer a standardized math test question where we are given the volume and the height of a cylinder and asked to find the radius. We will review that the...

In this short math video will find the measure of an angle of a triangle inscribed in a circle. We will review that if a triangle is inscribed in a circle and one side of the triangle is the diameter of the circle, then the angle...

In this short math video we will discuss similar triangles & proportionality. We will understand that if two figures are similar that their corresponding sides are proportional. We will identify the corresponding sides and write a...