Active Education Posts

How To: Understand the properties of real numbers

In this video, we learn how to understand the properties of real numbers. Natural numbers start at one and continue on and on. Zero is not a natural number. A whole number is just like a natural number, except it includes zero. Integers are the negatives included with whole numbers. There are no decimals included in integers. Integers also include positive numbers and no decimals with them, just whole numbers. Rational numbers are fractions and all decimals that end at a certain point. Once y...

How To: Be a human calculator

Before we had the calculator and before we had the abacus we had the human brain to complete our math problems for us. Remember that? Well, it seems that few of us do, resorting to calculators on our phone for elementary subtraction problems and multiplication.

How To: Rotate a shape about the origin 90° counter-clockwise

Davitily thinks that you can learn to rotate the images quite easily. In this video Davitily explains the process of rotating a geometrical shape about the origin. This rotation is counter-clockwise. Davitily explains the various steps involved in this process. Two steps are explained in this process. The explanation is very simple and done in a very interesting manner. This video is the perfect choice for people wanting to learn the rotation of shapes. This video is a must for people interes...

How To: Find the average value of a function over an interval

When you have to find the average of two or five numbers then you have to add all the numbers and then divide then by two or five respectively. However in the case of the function you have infinite many values over any interval. But it is not possible to add all and then divide by infinity. Therefore you have to calculate in a different way. Imagine that you have to find the average of y=f(x). Then you have to average it from the interval from ‘a’ to ‘b’. The inner area under the curve shall ...

How To: Use the Pythagorean theorem in geometry

Need help figuring out how to determine the length of the sides of a right triangle? Need to know how to solve a matrix-form linear equation in algebra? From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this installment from Internet pedagogical superst...

How To: Find the volume of a swimming pool

In this video, we learn how to find the volume of a swimming pool. To do this, you will first need to find the measurements of all the sides that are on the pool. After this, you will plug in the measurements that you found into the equation to find the volume. This equation is: V=AH, volume= area(height). So, plug in the area and the height to the equation for A and H and then multiply these two together. Once you do this, you will find the answer! Don't forget to label the units on the fina...

How To: Multiply Numbers by 9 Using Nothing but Your Fingers

From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this free math tutorial, you'll learn how to calculate the area of a triangle by formula. In this clip, you'll learn an easy finger-counting trick for quickly calculating multiples of 9.

How To: Simplify fourth roots

In this video the instructor shows how to find out the fourth roots of a number. The properties of fourth root says that for any positive number of a, its fourth roots are real. And for any negative value a, its fourth roots are not real. So split the number inside the fourth root as the product of two perfect squares and then cancel out the power with the fourth root giving its roots. As the fourth roots of a positive number are real, the answer you get is correct. But you cannot find out th...

News: The Silver Egg Illusion

This requires a dry hen's egg at room temperature. Hold an egg near a candle flame to cover it with soot. It will need to be completely covered. This is tricky, because if the egg is a tiny bit damp the soot will easily flake off on to your fingers as you turn the egg. Once the egg has a nice black sooty coating, gently immerse it in a bowl of water.

How To: Organize research materials for writing your research

Mary Silva teaches us how to organize and research materials for writing. First, copy and past all of your different references from the exact order that you wrote about them. A great way to help you organize all of these is to use notecards. If you don't want to do all that writing, then you can make your notecards on the computer! With this, you can make different notes on the bottom of the cards to help you remember things, as well as different citations. This is a great tool to help you o...

How To: Prove angle-side-angle congruency

This is a tutorial about how to prove the congruency (equality) of two triangles when the values of two angles and an included side of each triangle is given. The author of this video instructs the viewer that it should be first determined whether the values of two angles of one triangle are the same as those of two angles of the other triangle. Then one must seek to determine the equality of sides included in those angles in both the triangles. When it is found that these three values in one...

How To: Find a missing side of a triangle, similar to another

In this tutorial the author shows how to find out the missing side of a triangle which is similar to an other triangle. He explains the concept of similar triangle using diagrams and by showing that similar triangles have equal corresponding angles and parallel sides. Now he labels sides of similar triangles and intends to find out the length of unknown side. Now in similar triangles, as the lengths of sides are proportionate he shows how to write a equation of proportion and solve it finding...

How To: Find the area of quadrilaterals

Parallelogram is a quadrilateral in which both pairs of the opposites are parallel. To find the area of a parallelogram first draw the diagram of a parallelogram. Parallelogram can be further divided into squares and rectangles. To calculate the area of both of these kinds of parallelograms multiply the length of the parallelogram with its height. In general the area of a parallelogram in obtained by multiplying the base of a parallelogram with its altitude. In square and rectangle cases, the...

How To: Find the perimeter of a parallelogram

One thing that you will need to know in order to pass Geometry is how to find the perimeter of a parallelogram. Parallelograms are quadrilaterals with two pairs of parallel sides. It is not difficult to find their perimeter, but you will need to know a few steps. Check out this video for tips on how to do this in your math class and ace that big test.

How To: Use a protractor in geometry

Omar, Hayley, Gary, and Autumn teach us how to use a protractor. They give a bit of information from About.com on the history of protractors. They are used to measure angles. The first protractor was used to help with navigation and invented in 1801. To measure an angle, line up the base of the protractor with 1 line of the angle. The center circle should be on the vertex of the angle. Use the "swivel thing" to find what degree the other end of the angle lines up with. If there isn't one, you...

How To: Simplify Complex Fractions

The key to simplifying fractions is to convert the fraction from a hamburger to a hot dog. In other words you change it from a fraction to a division problem, and then use Keep,Change,Flip to simplify. The video explains all of this and helps make complex fractions,simple.

How To: Make Slimy Teenage Mutant Ninja Turtle Ooze at Home

It's been a minute since Michael Bay released his tragedy of a remake of Teenage Mutant Ninja Turtles. As a huge fan of the cartoon and the movies from the '90s, I have made it a point to not watch the latest this franchise has to offer—I'm certainly not in the business of ruining my childhood. But the awfulness of the remake aside, the TMNT resurgence means I'm celebrating the comeback of everybody's favorite teenage reptiles. Thankfully, Todd's Kitchen has a tutorial for mutant ooze that's ...

How to Be Your Own SpaceX: Design, Build & Test Liquid-Fueled Rocket Engines

Move over NASA— SpaceX is taking over. Well, not really. But today, the privately funded spacecraft company broke all expectations when their Dragon capsule fell to a soft landing in the Pacific Ocean, completing an undoubtedly successful demo flight of nearly two full trips around Earth. It was the first re-entry of a commercial spacecraft ever, bringing commercial space transportation closer to reality.

Classic Chemistry: Colorize Colorless Liquids with "Black" Magic, AKA the Iodine Clock Reaction

Want to make boring old colorless water brighten up on command? Well, you can control the color of water with this little magic trick. Actually, it's not really magic, but a classic science experiment known commonly as the iodine clock reaction, which uses the reactions between water and chemicals to instantly colorize water, seemingly by command. You can use different colorless chemicals to produce different colors, and you can even make the color vanish to make the water clear again.

How To: Make manganese dioxide electrodes

Various electrochemical reactions requires that anodes do not degrade when used. Carbon is cheap, but degrades easily and platinum is extremely expensive. In a previous video, you learned "How to make cobalt and manganese nitrates", and you saw that titanium could be used as a cathode, but not as an anode due to an effect called passivation.

How To: Here's How You Can Make a Real Difference in the Aftermath of the Michael Brown & Eric Garner Grand Jury Decisions

In the aftermath of the unindicted police killings of Michael Brown and Eric Garner, we've been told that the system worked as intended. When our legal system's outcome is at conflict with what a majority of Americans believe is just, it's clear that some changes are needed. But what specifically needs to change? And what can an average citizen with a moral and just cause do to prevent these kinds of tragedies from repeating themselves again and again?

How To: Solve ratio problems

Check out this instructional math video that demonstrates how to solve ratio problems. In the 14th lesson, learn how to solve SAT problems using the Official SAT Study Guide. Here are the math problems and their page numbers that this video covers:

How To: Evaluate numbers raised to fractional exponents

Looking for instructions on how to evaluate numbers raised to fractional powers? Learn how with this free video lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this free math tutorial, you'll learn how to solve problems involving numbers raise...