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How To: Calculate unit rates with basic arithmeitc

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 a unit rate.

How To: Apply exponent rules in basic algebra

Looking for a guide on how to work with exponents in algebra? 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: Factor polynomials in algebra using the GCF method

Need to know how to factor polynomials using the GCF method? Learn how 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: Use Maclaurin/Taylor series to find accurate integrals

See how to approximate a definite integral to a desired accuracy using Maclaurin/Taylor series and the alternating series estimation theorem with this free video calculus lesson. 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...

How To: Solve equations with the order of operations

In mathematics, the order of operations define the priority in which complex equations are solved. The top priority is your parenthesis, then exponents, followed by multiplication and division, and finally addition and subtraction (PEMDAS). This video tutorial demonstrates the order of operation with various examples and explains the associated methodology. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autod...

How To: Find the formula for a piecewise function from a graph

Need to know how to find the formula for a piecewise function from a graph? 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 and sketch the domain of a multivariable function

Looking for a primer on how to find and sketch the domain of a function z = f(x, y) in calculus? Learn how with this free video calc 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: Simplify complex fractions in algebra

Being circuitous and using ample euphemisms has gotten many a politan elected by the dumb and hated by the knowing. Though embellishing speech is often preferred in jovial presidential debates, mathematicians prefer to cut out the fat and get straight to the point.

How To: Find outliers using the Z-score method

If you use Microsoft Excel on a regular basis, odds are you work with numbers. Put those numbers to work. Statistical analysis allows you to find patterns, trends and probabilities within your data. In this MS Excel tutorial from everyone's favorite Excel guru, YouTube's ExcelsFun, the 49th installment in his "Excel Statistics" series of free video lessons, you'll learn how to find outliers with the +/- 3 Z-score rule and the ABS function. See how to do a box plot by hand and in Excel. For th...

How To: Apply the distributive property in math

To solve simple algebraic expressions you have to use different properties. Distributive property is one among them. To apply distributive property in a algebraic expression multiply each term inside the parenthesis by the outside term. In this way you are distributing the outside term to all the inside terms and removing the parenthesis. Hence it is called distributive property. After multiplying add the like terms to simplify it further. Care should be taken to ensure the proper sign change...

How To: Use a TI-89 to calculate nCr

This video shows you how to do a mathematical representation on computing the nCr function using a TI-89 calculator. You can write the nCr notation in different forms. It can be simplified from nCr to C(n,r). The symbol can either be read "n choose r" or "n taken r at a time" which are from it's probability applications. On the example to find "26 choose 17", go to the Home screen of the TI-89 calculator and then go 2nd 5 which is Math. Go choose probability and then to nCr to type in (26,17)...

How To: Figure out a tip without a calculator

To figure out a tip without a calculator, first remove the pennies amount in the bill. For example, if your bill is $23.76 becomes $23.70. To figure out a 10% tip, move the decimal point one place to the left. So, 23.70 becomes 2.370 or $2.37. Bump up that number to $2.30 or $2.40 or $2.50 cents, depending on your preference. Since 20% equals two times 10%, double the figure you computed for 10%. So, $2.30 becomes $4.60, or $2.40 becomes $4.80 or $2.50 becomes $5.00. Using this method, you wo...

How To: Solve an equation with a radical under a radical

In this video the instructor shows how to solve an equation with a radical under a radical. If you have an equation with a square root on both sides, with one of the sides having another inner square root under the original square root, it can be a little tricky to solve it.

How To: Factor a trinomial, GCF, then unfoil

In this video the instructor shows how to factor a polynomial. A polynomial having three terms is called as trinomial. Now if you factor it you will obtain two binomials whose product will be the original polynomial. Before factoring a polynomial you need to find out if the polynomial has a GCF. Look out for the common variables in all the three terms and pull them out which is the GCF of the polynomial. This simplifies the original equation to a polynomial which is of lower degree. Now facto...

How To: Find a missing coordinate given: coordinate & equation

In this video, the instructor shows how to find an unknown coordinate given the other coordinate of that point and the equation that passes thought the point. A point is said to lie on the graph, if the point can satisfy that equation of the line. To check if a particular point satisfies an equation, all you have to do is substitute the value of the point in that equation and check if it validates the equation. Now, substitute the given point with an unknown coordinate in that equation. If th...

How To: Simplify complex fraction w/ single fraction on bottom

This is a great instructional video on education. This educational video teaches you how to simplify a complex fraction with a single fraction on bottom. Let us learn this with an example. Let us assume we have to simplify the complex fraction 5 by x-4 divided by 5-4x by 5. When you simplify this you will get 5-4x over x divided by 5-4x over 5. You will now get 5-4x over x multiplied by 5 over 5-4x. This is equal to 5 over x. This is how we have to simplify a complex fraction with a single fr...

How To: Determine the age of a fossil using carbon-14

If you have a fossil, you can tell how old it is by the carbon 14 dating method. This is a formula which helps you to date a fossil by its carbon. If a fossil contains 60% of its original carbon, how old is the fossil? The half life of carbon 14 is 5600 years. That means this is how long it takes for half the nuclei to decay. After 5600 years, if we start with a gram, we end up with half a gram. This rather complex formula shows you how to solve this puzzle using accepted scientific methods.

How To: Solve percent equations

In this tutorial the instructor shows how to solve percent equations. The general form of a percent equations is that a is b% of c. As there can be three kinds of variables a, b, c, the questions involving percent equations can be of three types having one of the three variables unknown. These kind of percent statements can be solved easily by setting up an equation. So, to convert percent statement into a equation replace the unknown term with n, the 'is' term with equals sign and the '%' si...

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: Simplify square roots

This is a video tutorial on how to simplify square roots. To simplify square roots, one must have the knowledge of splitting numbers into prime factors. For example,12 can be split into 4*3 and further more into 2*2*3. Here we see that all the factors are prime numbers. So the square root of 12 can be written as 2*square root of 3(as shown in the video). The method used in the video is applicable for simplifying any square roots as any number can be split into prime factors. Follow the video ...

How To: Find the area of an oblique triangle using formulas

In this tutorial the instructor shows how to find the area of an oblique triangle using different formulas. To find the area of an oblique triangle there are different formulae. The first formula to calculate the area of a triangle is area A = (1/2) * a * b * Sin(C), where a and b are the lengths of the two sides of the triangle and C is the value of the angle of the triangle that lies in between the two sides a, b. Now substitute these values in the given formula to find the area if you have...

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 slope from a set of points

To find the slope of a line you must have two points and then you must plug in the two points into the slope formula. The slope formula is m= y2-y1 over x2-x1. If the slope is a fraction be sure to reduce to the lowest. Remember if a number is divided into zero it is zero, if zero is divided into the number it is undefined. A calculator can help one remember this. Horizontal lines have slopes and vertical lines do not. Drawing the lines on a graph can help you see the actual slopes and which ...

How To: Complete Fahrenheit to Celsius conversion

This video shows you how to convert temperatures from Fahrenheit(F) to Celsius(C). In the video, the example of 75 degrees F is used. The formula for converting Fahrenheit to Celsius is given by temperature in Celsius= (temperature in Fahrenheit- 32)/1.8. So for 75 degrees F we take 75 in place of temperature in Fahrenheit. Therefore the equation becomes (75-32)/1.8=C . Further 43/1.8=c and finally C= 24. Hence 75 degrees Fahrenheit= 24 degrees Celsius . This conversion is used as Celsius is ...

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...

Use the quadratic equation: finding the mirror point

In this video the tutor shows how to find the mirror point using a quadratic equation. He says that to graph a parabola you need to find the mirror point symmetrical to the Y-intercept. Now he explains how to find a mirror point using an example with sample values. He begins with saying that the Y-coordinate of the mirror point is same as the Y-coordinate of the Y-intercept. Now you have to find the x coordinate of the mirror point which he shows that it is double the x-coordinate of the vert...

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: 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: Find the sides of a 45-45-90 right triangle

First you want to find X using the identities given for a 45-45-90 triangle. When comparing the triangles in the video, we find that X must be 6. Next, use the identity to solve for the measurements of the sides of the triangle. In the video example, 6 is the length of the two sides and 6 times the square root of 2 is the length of the hypotenuse. The video is very short and does not explain a lot of things in detail, but that is because the examples are easy to figure out.

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 the slope given 2 points

This tutorial will show you how to determine the slope of a line if you are given two coordinates on a coordinate plane. You should first find the location of each point on the plane, remembering that the coordinates are in the format of x-axis (or horizontal movement), followed by y-axis (vertical movement). After plotting both these points, you should draw a straight line between these two points and then determine the slope of this line by taking the rise over the run of the line.

How To: Add and subtract variables

Math Problem Generator gives a video about how to add and subtract variables. All you have to do is combine the coefficient, which is the number that comes before the variable. The numbers are added or subtracted but the variable remains the same. In the video, the example given is 9x + 6x - x. First you add 9x + 6x, giving you 15x. The equation is now 15x - x. If a variable has no number written in front of it, that means the value is 1. So the equation is 15x - 1x and that is equal to 14x.

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: Write a slope-intercept equation given an X-Y table

In this tutorial the author shows how to derive a slope-intercept equation of a line given an X-Y table. He explains that the general form of slope intercept form which is y = m*x + b. Now he intends to find value of slope, i.e. m first. Now slope is change in y over change in x. He computes the slope using the X-Y values from the table. Next he substitutes a pair of x, y value in the equation to compute the value of y intercept b. Now finally substituting the values in the equation the slop-...

How To: Find the volume of a cone quickly

For people who are interested in math or who need to know how to find the volume of a cone for any reason, whether it be homework or architecture, this video will show you how to do so. The formula for finding the volume of a cone is (1/3) pi x radius^2 x height. You can find the radius of your cone by finding half the length across the center of the circle which is the cone's base. After plugging in all the values into this equation, you will be able to find the volume of any cone when given...

How To: Find the area of a triangle when given 2 sides & angle

This video shows you how to easily find the area of a triangle when you know the length of 2 sides and the angle between them. The first thing you have to do is mark the sides of the triangle by a, b, c, where a is the side between A and B, b is the side between B and C and c is the side between C and A. If you know 2 of these 3 sides an you know the angle between them you can find the area of the triangle very simple: Area= (a x b x sin c)/2, where a, b are the two sides and c is the angle b...

How To: Solve for the missing ratios or proportions

In this video the tutor shows how to solve the missing ratios or proportions. He explains it with an example, where a number in one of the ratios is missing and he intends to find this value. He shows the example of cross multiplication, where you multiply the values on the either side of the equation diagonally and finally solves the equation which results in the value of the unknown value. This is an introductory video explaining how to use rations and proportions to find missing values.