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How To: Solve word problems involving the Pythagorean theorem

See how to solve world problems involving the Pythagorean theorem in geometry with this free video math lesson from Internet pedagogical superstar Simon Khan. 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).

How To: Find the order of operations with fractions & decimals

In this video, the instructor shows how to find the order of operations with fractions and decimals. If you have an equation with both fractions and decimals, you can convert the decimals to fractions, or fractions to decimals to have the entire equation in either decimals or fractions. In this video, the instructor shows how to do this in either way. To convert fractions to decimals, just divide the numerator with the denominator. This method cannot be used if the decimals are repeating deci...

How To: Find the circumference of a circle quickly

In this instance we are going to Find the circumference of a circle by applying formula C=2pr where 'C' is circumference of a circle, approximate value of 'p' is 3.14 because it is irrational number and 'r' stands for radius i.e. half of diameter. So by applying this formula we can easily calculate circumference of a circle if radius is given or we can also calculate radius if circumference of a circle is given. One thing to remember is that unit we use for circumference of a circle is cm, in...

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: Calculate sums in standard form

When a number is expressed in the form of x multiplied by 10^y such that, x < 10 and y is an integer, the number is said to be in standard form. Standard form of expressing numbers finds its use in scientific and statistical fields. This video demostrates how to express, as well as perform basic mathematical operations namely, addition/subtraction, multiplication and division of numbers in the standard form using four examples/mathematical problems. The first two examples demostrate multiplic...

How To: Find the area of a ring w/ the areas of 2 circles

Doina Popovici's video explains how to calculate the area of a ring. She takes us really slow, down to all the steps of this process. It's very important that she explains every math formula and operation so you cannot get lost into this solving. The video uses nice pictures and colors in order to make learning easier and nicer for those who are interested. At the end of the video you'll surely be able to solve by yourself a problem like that and your appetite for geometry will grow significa...

How To: Subtract numbers on an abacus calculator

Lawrence Perez, from Saddleback College, and his assistant Charlie, give this two-part arithmetic lesson on subtracting with an abacus. Could this be any easier than adding? Maybe, can you "borrow" the knowledge to subtract these numbers without an electric calculator? See for yourself.

How To: Use an asymptote to find the equation of a hyperbola

Need instruction on how to find the equation of a hyperbola using an asymptote? 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).

How To: Solve rate-of-change problems with the chain rule

Looking for an easy way to solve rate-of-change problems? Use the chain rule! 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 superstar Salman Khan's series of free math tutorials, you'll learn how to calcula...

How To: Solve a set of linear equations with the TI-83

Looking for a guide on how to solve a system of linear equations using a TI-83 graphing calculator? 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).

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: Find the surface area of a pyramid

Finding the surface area of a pyramid is a bit different than finding the surface area of a 2D triangle. But, don't be scared, it is not as hard as it sounds. Have a look at this tutorial, and learn exactly how to find the area of a 3D object, specifically a pyramid. The good news is that once you have grasped the area of a flat triangle, that of its 3D counterpart should be pretty easy to learn.

How To: Use differential equations to solve for velocity

The guy first gives the definition of differential equations. He explains that a differential equation is an equation that contains the derivatives of an unknown function. He then gives some examples of differential equation and explains what the equation's order means. After that he gives an example on how to solve a simple equation. He calculates it and gives examples of graphs. Then he explains what a general solution is and how to narrow down the number of solutions using data from the pr...

How To: Calculate price per unit with basic arithmetic

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 installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to unpack and solve word problems that require you to find price per unit.

How To: Calculate the greatest common factor of a set of terms

Need to know how to find the greatest common factor or GCF for a set of numbers? 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).

How To: Solve percent proportions

A percent problem is one in which you are given a quantity and asked to compute the value of a percent of it. You may also be given the whole quantity and a part of it and asked to compute the percentage of the part in the whole. To do these kind of problems you need to use the rule which states that the ratio of the part to the base it equal to the ratio of the percent to hundred. That is part/base = percent/100. This comes from the definition of percentage which states that percentage is eq...

How To: Find the domains of rational expressions in algebra

Learn how to find the domain of 3 different rational expressions that have quadratic expressions in the denominator with this free video algebra 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 study for that next big test).

How To: Solve an algebraic equation with a fractional variable

Could you use some help figuring out how to solve equations involving fractions in basic algebra? See how it's done with this free video math lesson. Need help finding the 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 ...

How To: Use radical notation to evaluate rational exponents

Learn how to evaluate rational exponents using radical notation in this free video algebra 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 study for that next big test).

How To: Solve a word problem for the perimeter of a rectangle

Need a little bit of help figuring out how to solve word problems involving the perimeter of a rectangle? See how it's done with this free video math 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).

How To: Do matrix algebra with a TI-89 calculator

Looking for a primer on how to solve matrix problems using a TI-89 graphing calculator? See how it's done with this free video algebra 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).

How To: Find the number given its percent

This video will provide you with insight into how to find a number given its percent. In the example provided, you needed to find the number which 33 is 60% of. This was achieved by simply taking the number which is a percentage of another number, in this case 33, and divide it by the percentage, in this case 60%, or 0.6. By carrying out the long division from this step, you will be able to find the original number and solve this seemingly complicated problem with ease.

How To: Use probability to predict weather

In this video, we learn how to use probability to predict weather. Probability is the chance of something happening. If you want to know what the weather is going to be like, you can look at the weather report and see what each day is going to do throughout the week. Ask yourself what the probability is that the weather will be cloudy, judging from what the current work week weather is. First, figure out how many days there are total and then find out how many are cloudy versus how many are s...

How To: Find the surface area of a regular pyramid

In this tutorial, the instructor shows how to compute the surface area of a regular pyramid. A regular pyramid has four equal sides which are in triangle form, and the base in square form. Its surface area is four times the area of its side plus the area of its base. He goes on and takes an example with sample values and demonstrates how to compute the final value using the formula. He reminds the viewer to use square units in the final answer, as square units equal the area. To find out the ...

How To: Represent complex numbers with the Argand Diagram

Need a little help with your math homework? No problem, the Math Centre offers students video tutorials that will provide as a reference guide for self-study. Students get self-study resources targeted to the needs of individual courses, and teachers gain generic mathematics support and study materials for use with students.

How To: Find the volume of a cylinder

Need help calculating the volume of a cylinder? It's easy! So easy, in fact, that a complete and thorough overview of the process can be presented in forty-five seconds' time. Study for your next geometry test or just finish your homework with this free video math lesson, which demonstrates how to find the volume of a cylinder using v=pr^2h.

How To: Find the interior angle sum of a polygon

In this tutorial the instructor shows a method to compute the interior angle sum of a polygon. He gives us the formula for the interior angle sum of a convex polygon as (n-2) * 180 where n is the number of sides of the polygon. He goes and take a 6 sided polygon as an example and does the math by substituting the value of 'n' in the equation and arrives at the result. This video clearly gives the formula and demonstrates with an example of how to calculate the sum of interior angles of a poly...

How To: Divide a decimal number by another decimal number

Decimals are just as complicated as fractions, but they are written a bit simpler. In this video, learn how to divide a decimal number by another decimal number without a calculator. Follow the step by step presented in this tutorial and practice this method and it won't take you long to get it right everytime.