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How To: Add and subtract rational expressions in algebra

Need help adding and subtracting rational expressions in algebra? Grab a pen and hunker down with these practice problems. 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 a 2x2 system of linear equations with inverses

See how to solve a two-by-two system of linear equations using inverses (derived from determinants). 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: Use matrices to solve systems of equations on a TI83

This video shows how to use matrices to solve systems of linear equations on TI83 and TI84 series graphing calculators. 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 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: Antidifferentiate functions with radicals in calculus

This video demonstrates how to do anti-differentiate functions with radicals in calculus. To simply problems, try to substitute. For example, in the problem, the integral of x times the square root of x plus 2 dx. You can substitute w for everything underneath the radical: i.e. x + 2. When you simplify, it becomes: the integral of x times the square root of w dw. Now, you need to get rid of the x, which you can do with a substitution: w – 2 = x. Now, plug in the values and simplify it.

How To: Fill a cone

This is a very interesting instructional video on how to fill a cone. Pour oil into a cone of diameter 30 inches and depth 40 inches. Now find the volume of the oil as a function of its depth. Volume = 1 over 3 phi rsquare h. We don't know the height and depth of the oil poured into the cube. Draw similar right angled triangles. In one right angled triangle the height is 40 inches and in the other triangle it is h. Similarly the height is 40 inches and h respectively. Now rover h =15 over 40....

How To: Find the area of a right triangle using simple math

It is easy to find out that right triangle is only half of the square. And again there is a rectangle with a triangle shaded in red color. The red triangle is half the area of the rectangle. But to calculate just the area of triangle, we can calculate the area of the rectangle whose area is length times width. When we have a rectangle with its length and width as 4u and 2u respectively then the area of that rectangle will be equal to 8u(squared). But we already know that the triangle is half ...

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: Evaluate a line integral along a straight line segment

This video tutorial is in the Education category which will show you how to evaluate a line integral along a straight line segment using the definition of the line integral. This video evaluates a line integral along a straight line segment using a parametric representation of the curve (using a vector representation of the line segment) and then integrating. A vector representation of a line that starts at r0 and ends at r1 is r(t) = (1-t)r0 + tr1 where t is greater than equal to 0 and lesse...

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: Factor & find zeros of a polynomial

This is the video about how to Factor & find zeros of a polynomial. How did I know that x=1 and x=-1 were roots of the polynomial. Suppose the polynomial has a rational root, let's call it. I will assume that p and q are co prime, i.e., the fraction is reduced to lowest terms. What we will be doing is somewhat similar to "factoring by guessing" of quadratic polynomials. Since is assumed to be a root of P(x), we know that if we multiply both sides by, we obtain: Transfer them to the other side...

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 area of a trapezoid

Get help with your math homework and learn to find the area of a trapezoid by watching this video. Following along while four examples are solved, the viewer will learn how to calculate the area when all the required measurements are given and will learn to calculate distance of one side when the area of the trapezoid is known. If you are learning about measurement in school or are trying to find the areas of a trapezoid for another reason (maybe you are carpeting an oddly shaped room), this ...

How To: Change mixed numbers to improper fractions

In this Math tutorial, you will learn how to convert a mixed number into an improper fraction. The narrator explains the process in a very concise yet simple manner that will make math problems involving mixed numbers so much easier to solve. The general idea is to multiply the whole number with the denominator and then add that to the numerator. The explanation and illustration in the video makes it easy to understand.

How To: Find the vertical asymptotes of rational functions

To find a vertical asymptote, you are trying to find values of x that produce 0 in the denominator but not in the numerator. If 0/0 occurs, that means you have a "hole" in the graph. A vertical asymptote is a place in the graph of infinite discontinuity, where the graph spikes off to positive or negative infinity. To find the vertical asymptote, set the denominator equal to zero and solve for x. Check that the values also do not give a zero in the nominator. If the values work, you have found...

How To: Find the standard deviation with the Z-Score formula

In this tutorial, we learn how to find the standard deviation with the Z-Score formula. First, take your problem and write it out one by one underneath each other. Then, you will need to substitute the numbers in for the variables that are in the problem. Once you do this, you will follow the basic rules of math to find out what the answer to the problem is appropriately. Once you have done this, finish off the problem to find the answer, then you will have found the standard deviation using ...

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: Find the circumference of a circle

Use a simple mathematical formula to find the circumference of a circle. The circumference of a circle can be determined by using the formula 2 times pi times the circle's radius. Pi is equal to 3.14. If a circle's radius is 10 centimeters, first multiply pi times 2. Pi, or 3.14, times 2 is 6.28. The next step then is to multiply 6.28 times the circle's radius. Since the circle's radius is 10 centimeters, multiply it by 6.28. This gives you 60.28. 60.28 inches, then, is the circumference of t...

How To: Find a slope of a straight line with: Ax + By + C = 0

In this video the instructor shows how to find the slope of an equation which is in the form Ax + By + C = 0. He says that the formula to find the slope of a line in the above form is slope m = -A/B, where A and B are the numeric constants of the variables x and y in the given equation. He goes on and further shows how to do this with a couple of examples. He shows how to reduce any equation into the general form and how to apply the slope formula then. This video shows how to find the slope ...

How To: Do normal probability calculations on a calculator

Probability computation is a complex process and even using a calculator can be difficult. But normal probability calculations can be performed quickly with the help of calculator once you know how to use it. So when you have to calculate a probability from a normal distribution you can use the functions on your scientific calculator. You can use the normal CDF function from you calculator to compute the area under a normal curve. The function requires lower band and upper band values, the me...

How To: Calculate percent yield

This video shows you how to calculate the percentage yield in chemistry. To find the percentage yield, you will need to divide the actual yield by the theoretical yield. Then, multiply it by 100: i.e. % yield = actual yield/theoretical yield x 100. An actual yield is the amount of a substance produced in an actual laboratory experiment. It is based on an actual physical measurement of a quantity. The theoretical yield is the yield as is calculated on paper: i.e. through calculations. Therefor...

How To: Find the area of a circle with a given radius

This video describes how to find the area of a circle given a radius of 4cm. The video begins by describing the formulas needed to find the area of the circle. The narrator cautions the viewer on a few common mistakes that people frequently make while using these formulas, such as not properly squaring the radius of the circle. The solution to the formula for a 4cm radius is 50.24 cm^2. The video then demonstrates that this value makes sense by overlaying a grid onto the circle and visually s...

How To: Simplify a quadratic formula result

In this video the tutor shows how to simplify a quadratic formula result. You can solve a quadratic equation using the quadratic formula. The first thing you have to do when given the quadratic equation is bring all the terms to one side so that you have a zero on the other side of the equals to sign. Now the formula to calculate the roots of the quadratic equation ax*x + bx + c = 0 is x = (-b + root of(b*b - 4*a*c) ) / 2 * a. The other root can be obtained by using the minus sign before the ...

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: Remember "greater than" & "less than" symbols

This video shows you how to easily remember "greater than" and "less than" math symbols. The first thing you have to remember is that "less than" symbol looks like the letter L ("less than" symbol is "<"). When you see this sign, remember that < looks like L and means "less than". The other symbol, "greater than" does not look like the letter L, therefore it cannot be "less than" and it's easier to remember. The "greater than" symbol is ">". That's it! Good Luck!

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: Find the equation for a growth pattern

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 find an equation that describse the growth pattern of a sequence of blocks.

How To: Factor quadratic expressions using trial and error

Sometimes there's no better way to factor a quadratic equation than by simple brute-force trial and error. Watch this free video algebra lesson to see how it's done. 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: Figure out the domain & range of a piecewise function

Need to calculate the domain and range of a graphed piecewise function? 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: Calculate percentage with a calculator

This easy to understand video gives us two ways to calculate a percentage using a calculator. The video first shows us how to use the percent key on the calculator using the example of figuring out how much to tip at a restaurant. We can also convert a percentage to decimals before entering the information in the calculator and then just use simple multiplication. The instructions are easy to follow, as the video is less than a minute of watching someone use a calculator.

How To: Calculate percentages in your head

This video explains how to calculate percentages in your head. To calculate a percentage in your head, start by breaking the percentage off into smaller units. For example 25% is 10 + 10 + 5. 30% is 10, 10, and 10. Now you have numbers you can easily work with in your head. Find 10% of the number. This is easily done by one of two methods. You can either move the decimal point one place to the left or you can drop the last number. Dropping the last number sometimes gives you an estimate, thou...