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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: 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: Find the equation of a circle given: center & tangent

In this video, the instructor shows how to find the equation of a circle given its center point and a tangent line to it. To do this, take a graph and plot the given point and the tangent on that graph. Now, from the center of the circle, measure the perpendicular distance to the tangent line. This gives us the radius of the circle. Using the center point and the radius, you can find the equation of the circle using the general circle formula (x-h)*(x-h) + (y-k)*(y-k) = r*r, where (h,k) is th...

How To: Find the perimeter & area of a complex figure

In this video tutorial the author shows how to find the perimeter and area of a complex figure. He shows that a complex figure can be subdivided into standard geometric figures. In the current example he divides the complex figure into a rectangle and a triangle. Now he computes the perimeter by adding the three sides of the rectangle and the two sides of the triangle. Similarly he computes the individual areas of the rectangle and the triangle and finally adds then up to find the area of the...

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: 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: Use ">" (greater than) and "<" (less than) symbols

In this video the author explains how to identify the less than (<) and greater than (>) symbols and when to use them. She explains to us to relate the numbers to animals stating that the smaller numbers are smaller animals and bigger numbers are bigger animals. Now she tells us to imagine that smaller animals are eaten up by the larger animals. So she shows a smaller number comes on the left side of '<' sign and bigger number comes on the right side of '<' sign stating that the bigger number...

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: Find the area of a circle when you know the diameter

In this video, it is shown how to calculate the area of a circle where the diameter is given. The formula for calculating the area of a circle is pi multiplied by square of radius. Radius is actually half of the diameter. In this video, the diameter is given as 10.6 meters. Hence, the radius will be half of 10.6 which is equal to 5.3 meters. Now, to find the area we shall multiply pi with the square of 5.3. Square of 5.3 is 28.09. If we multiply 28.09 with pi we shall get the area of the circ...

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.

How To: Multiply & Divide Numbers (Basic Elementary Math)

Adding and subtracting may be the easiest of mathematical operations, but once you get it down, multiplication and division can be just as easy. That's why it's called elementary arithmetic. If it were harder, it would be called college algebra or trigonometry. But it's not— it's basic math, and once you get your head around the numbers, you'll never hate math class again! (Okay, maybe you will.)

How To: Find extra points for a parabola (quadractic equation)

This is a mathematical educational video on how to find extra points for a parabola. In the first two examples there is no need for finding extra points as they have five points and have zeros of the parabola. In example 3 we need to find extra points. The equation is y=4xsquare-4x+4. You can take x= -1 and get the value for y. You will get a point now. Similarly you can substitute -2 for x in the same equation and get the value for y. Now you get another point. Now you can draw the parabola.

How To: Find standard deviation

In this video tutorial, viewers learn how to calculate the standard deviation of a data set. The standard deviation of a statistical population, a data set, or a probability distribution is the square root of its variance. To calculate the standard deviation, users will need to follow these steps. 1) Find the mean of the data. 2) Subtract the mean from each data point. 3) Square each of the values you got in step 2. 4) Then find the mean of the values you get from step 3. 5) Finally, square r...

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: 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...

How To: Add and subtract rational expressions in algebra

In this math tutorial, you'll be trained in the arcane art of adding and subtracting rational expressions by finding the common denominator. A skill many discard upon leaving middle school, it is used by the villians who operate under the acronym "SAT" to test those caught blank minded and whose minds are unrationalized.

How To: Identify characteristics of a sample during a survey

To identify characteristics of a sample in your survey, there are many factors to consider of your samples. The first four characteristics you need to focus on are gender, age, income level, and education level. All four of these characteristics must be proportional to that of the population. You also need to consider the geographic location. Only take samples from the immediate geographical area. Finally, an important characteristic of the survey is the sample size. You do not want to ask to...

How To: Subtract mixed numbers with borrowing

This video teaches you to subtract mixed numbers with borrowing. Consider 2 mixed numbers. For example 8 and 2/7 and the other 5 and 4/5.You have to subtract 5 and 4/5 from 8 and 2/7. First you have to convert the fractions to their common denominator. To equate the denominators of these two fractions you have to multiply the first denominator with the numerator and the denominator of the second fraction and also multiply the numerator and denominator of the first fraction with the denominato...

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: Find the equation of a line given 2 points

This tutorial teaches you how to find a mathematical equation of a line given 2 points that exists on the line. The tutorial starts off with 2 points labeled (2,-4) and (3,6). The first step is to determine the slope of the line using the formula given in the tutorial in blue. The slope is then solved as 'm'. Plug the slope and the points into another formula given in green. The tutorial maker provides a tip that one can use x1 and y1 or x2 and y2, however, it must be consistent. After, solve...

How To: Calculate the area of a parallelogram

Calculating The Area Of A Parallelogram A parallelogram is a 4-sided shape formed by two pairs of parallel lines. Opposite sides are equal in length and opposite angles are equal in measure. To find the area of a parallelogram, multiply the base by the height. The formula is:

How To: Find the surface area of a cylinder easily

In this video tutorial the author shows how to find the surface area of a cylinder. He shows a four step approach to solve this problem. First he gives us a formula to find the surface area of a cylinder, where Surface area A = 2 * Pi * R * R + 2 * Pi * R * H, where R is the radius of the base of the cylinder and H is the height of the cylinder. Now he identifies those values and substitutes them in the formula giving the surface area of the cylinder. This video shows how to compute the surfa...

How To: Graph inequalities on a number line

In this video, we learn how to graph inequalities on a number line. Inequalities have a greater than or less than sign instead of an equal signs. Remember that these are no different than figuring out how to graph normal equations. First, you will need to remove the single numbers from each side of the equation. Continue to do math on the equation until you figure out what 'x' is. From here, draw the numbers on your graph and then find the number that 'x' is greater to or less than. Use an op...

How To: Determine if you have a function

In this tutorial, we learn how to determine if you have a function. You will start off with two functions and their points. The 'x' values make up the domain of the function and the 'y' values make up the range. The input values are the domain and the output are the range. If you're checking to see if you have a function, you will need one 'y' for every 'x'. This means that each value has another one that goes with it. Each of the points need to have one partner with them, no more and no less...

How To: Solve word problems containing radical equations

See how to unpack and solve a word problem containing radical equations 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: Use and find x & y-intercepts in algebra

A straight line can be represented in the form of a liner equation containing two variables x and y. When the equation is graphed on a pair of coordinate axes, the line passes cut through the axes in two points. The point where the line cuts the x-axes is called as its x coordinate and the point where the line cuts the y-axes is called as its y coordinate. In this way a line has x-intercept and y-intercept. The x-intercept of a line lies on x axes and is in the form (a,0). Similarly the y-int...

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: 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: 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: Factor trinomials using the Berry factoring method

In this free video math lesson YAY MATH, we learn how to factor trionmials using the Berry method. With mathematics, as with anything else, not everyone progresses at the same rate. Algebra is no exception. Happily, in the age of Internet video tutorials, this isn't a problem. Those who progress quickly can go beyond what's being taught them and those who are struggling likewise have all the time in the world to catch up. Whether you need help finishing your homework or studying for that next...

How To: Divide numbers with exponents

In this tutorial, we learn how to divide numbers with exponents. The quotient rule states that we can divide two powers with the same base by subtracting the exponents. With the same base, you can subtract the exponents to get something that would be the answer. For example, if you have 6(to the fourth) divided by 6(to the second), this would come to equal 6(to 4-2). This would break down to equal 6(to the second power). Once you have this, you will be able to do the math for this and figure ...

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...

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