Hot Education Posts
How To: Make a candle wax explosion
In this video, you'll see how and why wax can be a deadly. This is how it works,When the test tube is submerged in cold water, the glass forms tiny cracks. The Water enters gets into the tube and vaporizes causing a micro explosion. The hot wax is then ejected from the tube quickly as oxygen is displaced from the tube itself. Be careful, and make sure to be as safe as possible when trying this experiment at home.
How To: Multiple and divide rational expressions
This video walks you through the steps of multiply and divide rational expressions. This excellent video shows you a clean board, with the instructors voice showing exactly what to do. Don't fret, any question you may have, will be answered. Watching this video will make you feel like your back in the classroom but rather comfortably from your home.
How To: Apply zero, negative, and fractional exponents
This video walks you through the steps of applying zero, negative, and fractional exponents. This excellent video shows you a clean blackboard, with the instructors voice showing exactly what to do. Don't fret, any question you may have, will be answered. Watching this video will make you feel like your back in the classroom but rather comfortably from your home.
How To: Find the equation of a perpendicular & parallel line
This video shows how to find the equation of the line perpendicular and parallel to a given line. The video starts off with an example, given the lines and the slopes (m). When 2 lines are parallel to each other, they have the same slope. When 2 lines are perpendicular to each other, the slopes multiplied together will give -1. Knowing these rules, the tutorial maker provides an example with numbers. He then leads each step of the process. Each step is written out in either black, red, blue o...
How To: Make "Hot Ice" with Sodium Acetate Crystals
If you've ever used a heating pad or hand warmer, you essentially know what "hot ice" is. It's supersaturated sodium acetate, and it's actually fairly easy to make at home out of sodium acetate crystals. You can also make it out of vinegar and baking soda (directions at the bottom of this article).
How To: Factor trinomials with the "swing method"
This is a very interesting educational video on how to find the factor trinomials using the swing method. Let us take an example and find the factor trinomials for 2xsquare-13x-45. Let us use the swing method. So now we will get 2xsquare -13x-45. You have to find the suitable factors of 90. It is 18 and 5. If you multiply 18 by 5 you will get 90. You will get (x-18over2)(x+5over2). The final answer is (x-9)(2x+5). Now we have found out the factor trinomials of 2xsquare-13x-45. This swing meth...
How To: Make hydrogen gas & an explosion
First you need to make hydrogen gas which require a few material. Such as a glass bottle, a Full table spoon of aluminum (beer or soda can will work), a half a cup of cold water, a table spoon or two of caustic soda, a funnel, a medium size container of water, a way of cutting the aluminum, one or two balloon's, and some safety glasses just incase something goes wrong.
How To: Graph a line using slope intercept form
A basis of algebra, slope intercept form can easily bring your equation to a graph with ease. This video will show you exactly how to graph equations using the slope intercept form.
How To: Simplify radical expressions
In this video the instructor shows who to simplify radicals. If you have a term inside a square root the first thing you need to do is try to factorize it. First factorize the numerical term. Write down the numerical terms as a product of any perfect squares. Now split the original radical expression in the form of individual terms of different variables. Now you can pull out the perfect square numerical factors out of the radical. Similarly for the variable terms write the variables as power...
How To: Find the formula of a piecewise function given a graph
This video shows how to find the formula of a piecewise function when given a graph. The first step is to write a definition for the graph, which is done by identifying the different domains shown in the graph. The second step is writing formulas for each domain specified by the lines in the graph. The point-slope formula is used to identify the slope and y-intercept for the leftmost domain, which has a sloped line. A point and horizontal line make for simpler equations in the other pieces of...
How To: Write a sum/difference of logarithms as a logarithm
To write the sum or difference of logarithms as a single logarithm, you will need to learn a few rules. The rules are ln AB = ln A + ln B. This is the addition rule. The multiplication rule of logarithm states that ln A/b = ln A - ln B. The third rule of logarithms that deals with exponents states that ln (M power r) = r * ln M. Using these three rules you can simplify any expression that involves logarithms to arrive at a single logarithm. The instructor shows how to apply these rules to a f...
How To: Do long division without a calculator
This video shows you step by step how to do long division without the use of a calculator. The video shows viewers two different ways to solve a division problem. It first shows how to do the problem the traditional way, then it shows how to do it according to the long division process. The long division process is where you write the whole division, multiplication, and subtraction process out showing all your work. Long division is mainly used when dividing large numbers. There are three com...
How To: Change Fahrenheit to Celsius
This video is a tutorial on how to convert Celsius to Fahrenheit. The title of the film says it will teach you how to convert Fahrenheit to Celsius, but it does not. It does just the opposite. The video begins by comparing Fahrenheit and Celsius. He points out that Fahrenheit measures water to freeze at 32 and water to boil at 212. Celsius measures water to freeze at 0 and water to boil at 100. To convert Celsius to Fahrenheit, multiply the Celsius temperature by 1.8 and add 32. Many countrie...
How To: Divide decimals
Here we are, learning how to divide decimals. So we are dividing a whole number or a fraction by a fraction. How this presenter does this is by moving the decimal two places to the right on both the top and bottom of the sum. In other words, he multiplies the two numbers by 100. So 2 becomes 200 and .25 becomes 25. So much easier to divide 200 by 25 than to divide 2 by .25. Provided you've multiplied both the top and bottom by the same amount, the result will be the same, because the relative...
How To: Determine the density of salt water
Everyone floats in the Dead Sea because the amount of salt in water effects the density. Do a hands-on experiment and practice checking density. Here’s a good science experiment to do in class or at home, if you have access to an electronic balance.
How To: Simplify a complex fraction w/ binomial denominators
To simplify a complex fraction, turn it into one fraction on the top divided into a fraction on the bottom. Once this is complete, you will turn the division into the two into a multiple by the reciprocal, factor, and then cancel. To make a division, find the lowest common denominator of both the top and the bottom. Once you get this division equation, look carefully at the equations. If something can be easily canceled, go ahead and cancel it out at this time. If you cannot cancel anything a...
How To: Purify manganese sulfate contaminated by iron sulfate
In a previous video by NurdRage, he showed you how to make manganese sulfate ("How to make MnSO4 from MNO2 (two separate ways)"), but there can be situations where the iron in the precursor would carry over and contaminate the product. Recrystallization doesn't work for this high level of contamination, so a different approach is needed.
How To: Evaluate logarithms using a calculator TI-83
A video to help calculator users find the natural logarithm (log base e, or "ln") and standard logarithm (log base 10, or simply "log") of any number using a TI-83 calculator (works for any issue of the TI-83 calculator or even a TI-84 calculator). Turn on your calculator. To find the natural log of a number, press the "ln" button (the third button from the bottom left), enter the number you want to find the natural log of, press the ")" (closed parenthesis) button, then press enter. The same...
How To: Make MnSO4 from MNO2 (two separate ways)
What is MnSO4 and MNO2, anyway? They are they molecular formula for Manganese Sulfate and Manganese Dioxide. And you can make one from the other. But how?
How To: Graph the greatest Integer or floor function
The video shows the explanation of greatest integer function. This video explains this with the help of graphs. The video first describes the basic greatest integer function. This means the greatest integer less than or equal to the number gave. The graph of this function is drawn. The video then shows the variations of this function. The first variation shows the function that replaces the 'x' coordinate with it subtracted by three. This shifts the graph to the right by three units. The seco...
How To: Find the x & y intercepts of rational functions
In this tutorial the instructor shows how to find the x and y intercepts of rational functions. Finding the intercepts of a rational function is similar to finding the intercepts of other normal equations. You can find the x intercept of the equation by setting the value of y to zero and solving the equation. Similarly you can solve the y intercept by setting the value of x to zero and solving the equation. Now while solving this rational function for intercepts if you face a situation where ...
How To: Find the opposite and absolute value of a number
View the absolute value of a number as its distance from zero. When you take the absolute value of a number, you always end up with a positive number (or zero). Whether the input was positive or negative (or zero), the output is always positive (or zero). For instance, | 3 | = 3, and | _3 | = 3 also. This property that both the positive and the negative become positive makes solving absolute-value equations a little tricky. But once you learn the "trick", they're not so bad. Let's start with ...
How To: Draw a rhombus from Geometry
In this video the author shows how to draw a rhombus when given with the values of long diagonal (D) and a short diagonal (d). Now he draws the long diagonal of size D horizontally on a sheet of paper. Now he points the mid point of the line as he explains that the diagonals of a rhombus meet at midpoints. So now he takes the ruler and draws an another line perpendicular to the first line through its marked mid point such that the length of the perpendicular line is d/2 both above and below t...
How To: Use a mean and scatter plot for Statistics
Wondering how to use a mean and scatter plot for statistics? Just follow the few simple steps as below.
How To: Graph an inequality on a number line in Algebra
The video described here from [free math tutoring Freemathtutoring] teaches how to plot natural number on a number line in different situations. First, the author defines natural numbers, integers and real numbers. He then teaches different methods on how to plot natural numbers on a number line. The most important fact to remember is that natural numbers are greater than 0; they do not include negative numbers. Like wise, he explains different situations to plot natural numbers on a number l...
How To: Figure out and calculate sales tax
Video describing about how to calculate a sales tax price based on purchase price and sales tax percentage. There is one example which is described as below:
How To: Draw a right trapezoid in Geometry
Watch this video to learn how to draw a right trapezoid using given specifications for lengths of sides. A right trapezoid is a four-sided shape with two right angles and two parallel sides. First, draw the long base. Then draw a 90 degree angle at one end of the base, using a protractor. Mark the angle to show it is 90 degrees. Then draw another 90 degree angle at the top. This is the first video in a set--to finish learning you must watch the next segment. If you watch these videos you will...
How To: Test manganese dioxide for purity (and sand)
This video speaks to everyone who has ever bought anything online, or in fact, anyone who has ever bought anything period. How do you know what you're getting is genuine? Is it a fake product? Is it stolen goods? Is it impure?
How To: Solve multi-step equations with absolute values
This educational math video describes the steps necessary to solve an equation involving absolute values. "Absolute value" refers to the magnitude of a quantity and is always expressed as a positive number. You can think of absolute value as the distance a number would be from zero if plotted on a number line. Positive 17 and negative 17 both have the same absolute value because both are 17 units from zero on a number line. Because of this, all absolute value problems have two answers, one wh...
How To: Break a yardstick with atmospheric pressure
This video shows you how to break a yardstick with atmospheric pressure. The instructor first lays a ruler halfway on and off of a table. He then covers half the ruler with newspaper. The instructor states that you can chop the ruler in half with your hand because the air holding down the paper will keep the ruler in place. The experiment does work correctly and he did break it in half perfectly. This instructor seems to have many similar videos on the subject.
How To: Graph by using an X-Y table
In this video the author shows how to graph using an X-Y table. He shows how to do this with a sample equation. He builds a table of x, y values where he takes sample values for x like -1, 0, 1 and now he substitutes these values in the equation of the line and obtains the corresponding y values. Now finally he has an x, y value table which now he shows how to plot it on a coordinate plane. He plots all the three pairs on the graph and connects them with a line finally obtaining the resultant...
How To: Find the volume of a cylinder quickly
In this video the tutor shows how to find the volume of a cylinder. He relates the cylinder to real world examples of cans etc. Now he states the formula of the volume of the cylinder as the area of the base circle multiplied by the height of the cylinder. So the formula turns out to be V = Pi * r * r * h, where r is the radius of the base circle and h is the height of the cylinder. He solves a sample example to give you the idea of the problem. This video shows you how to find out the volume...
How To: Convert units of measurement
This video shows you how to easily convert units. The first step you have to do is setup a proportion between a known conversion (e.g.. convert 2.5 km to m: 1km = 1000 m, => 1 km/1000 m = 2.5 km/X m). The second step you have to do is solve the equation by taking the cross product and find out the missing value (x). (e.g.. 1 km/1000 m = 2.5 km/X m <=> 1 x X = 1000 x 2.5 <=> x=2500 m). That's it! Good Luck!
How To: Calculate percentages
Learn how to calculate percentages with this easy video tutorial! One of the easiest way to calculate percentages is as follows:
How To: Divide small numbers by big numbers
This is a mathematical educational video on how to divide a small number by a larger number. You are aware that it is easy to divide a larger number by a small number. For example, if you want to divide 379 by 9 it is easy to do so. But if you have to divide 9 by 379 it is a bit difficult. You have to add a zero and see if you can divide. You need to add one more zero so that you can divide 900 by 379. But you should know that the answer would start like this 0.0 as we have added 2 zeros alre...
How To: Calculate percent composition for chemistry
To calculate percentage composition we will take the example CO2 it stands for Carbon-Di-Oxide. It is the composition of Carbon and Oxygen. We have one carbon and its weight is 12.01 and 2 oxygen. So, we will multiply 2 with 16.00 which is the weight of the oxygen.
How To: Purify hydrochloric acid
This video topic was changed. It is now converting muriatic acid to reagent grade hydrochloric acid, HCL).
How To: Use the percentile formula in Statistics
In this tutorial the instructor explains the percentile formula. He says that the percentile formula is used to find the percentile rank of a data point in a group of data. He takes an example that consists of the lengths of puppies. Now he intends to find out the percentile rank of any puppy in the group. He shows that the formulate to compute a percentile rank of a particular puppy is rank R = 100 * (N< + (1/2)N= )/ Nt, where N< is the number of puppies whose length is less that the length ...
How To: Find a number given Its percent
This how-to video is about how to find a number when its percent is given. This video is really helpful and effective in finding the number when the percent is given, the following steps are explained in the video to find the number when its percent is given:
How To: Apply the distributive property
The distributive property is a very important factor to consider in math and may save you a lot of trouble on your math homework. For values which lie right outside parentheses, you will need to distribute this value across the contents of whatever is inside the parentheses. You will need to multiply the value outside of the parentheses by first the first term inside the parentheses and then by the following terms inside the parentheses, distributing the value across all the terms found insid...