Math Features
How To: Convert temperature measured in Celsius to Fahrenheit
This video teaches how to convert a value in Celsius to Fahrenheit in simple steps. First take a paper and marker and keep in mind a Celsius value (e.g-32) to convert into Fahrenheit. Now use the formula to convert Celsius to Fahrenheit which is F=1.8(32)+32. Use a calculator to calculate the formula and you will get the result as 89.6 Fahrenheit. Now round it off the and your final result will be 90 degree Fahrenheit.
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...
News: Encrypting Passwords With an Old-School Tabula Recta
Have an old-school tabula recta lying around? No? Then just print out the chart below. Nothing ensures better password security than this centuries-old cipher technique. Here's how it works, via Wikipedia:
How To: Find abc, curve direction & y-intercept (quadratic eq)
In this tutorial, we learn how to find abc, curve direction & y-intercept (quadratic eq). First, you need to find the a,b, and c of the equation. A will equal what the coefficient is in the equation, B will equal the second, and C will equal the third term. This tells us if the numbers are positive or negative, so so know if the parabola opens up or down. To graph C, you will know what the y-intercept is going to be, then find the matching units. After this, you will use B to shape the parabo...
How To: Convert scientific notation to standard algebra form
Learn how to convert from scientific notation to standard form by watching the above math video. To change a number from scientific notation to standard form, move the decimal point to the left (if the exponent of ten is a negative number), or to the right (if the exponent is positive). You should move the point as many times as the exponent indicates. Do not write the power of ten anymore.
How To: Draw the "y=A|x-h|+k" graph
In this video, one teacher talked in detail about how to solve absolute value functions and how to translate different absolute value functions from one point in the matrix to another one horizontally and vertically. If the function is y=A|x-h|+k, generally, the diagram is symmetric based on the line of X and can be moved vertically based on k. The teacher gave several examples to explain how to illustrate the absolute value function. He started with a simple one: y=|x-h|, then continued with...
How To: Simplify a radical expression including variables
Want to simplify a radical expression with algebraic variables? 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 study for that next big test).
How To: Solve a system of linear inequalities via elimination
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 solve a system of linear inequalities by elimination.
How To: Solve multi-step and compound inequalities
Multi-Step inequalities are inequalities which take more than one step in solving them. You need to follow a step by step approach in solving these kind of problems. Through there is no general method to solve them you can follow a set of guidelines. First thing you have to do is make sure that only x terms remain on the left hand side of the equation. If there are any other numerical terms add the negative of that term to both the sides of the equation to eliminate it on the left hand side. ...
How To: Factor a trinomial with a negative in front
This video shows the method to factor a trinomial with a negative sign in the front. The first step is to make the first term positive. This is done by taking the negative sign out. Then we see the middle term of the trinomial. The coefficient of the middle term is a positive one in the example shown. We have to group the coefficient of the first and third term in a way so that the difference is positive one. The appropriate combination is chosen so that this becomes true. In this way the tri...
How To: Plot absolute values on a number line
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 plot absolute values on a number line in simple algebra/geometry.
How To: Do long division
For anyone who has ever struggled with long division, this video offers some tips on how to perform this seemingly daunting task with relative ease. The example provided in this video is a very useful one and by following the steps of this video, you will be able to do long division easily. Starting from the right side of the number which is being divided, add 0's as place holders until you arrive at a number which can be divided by the number you want to divide by. Perform this one simple di...
How To: Solve percent problems
Percent problems, also called as proportion problems, are simple problems where you deal with percentages. Given a percentage problem you may need to identify the percentage, the part or whole quantity from it. You can use the proportion or percent equation to do this. Proportion equations says that the ratio of part to the whole is equal to the ratio of percentage to one hundred. Percent equation says that the product of the percentage in the decimal form and the whole gives you the quantity...
How To: Simplify complex fractions in math
In this tutorial the instructor shows how to simplify complex fractions. A complex fraction is the same as a normal fraction, but has a fraction problem in the numerator and a fraction problem in the denominator. The first thing to do is arrive at a simple fraction both in the numerator and the denominator. To do this take the lcm of the denominators of the fractions in the numerator and simplify it. Similarly do this in the denominator. Now both the numerator and the denominator have a simpl...
How To: Solve the circumference of a circle using a cookie
In this video the instructor shows you the diameter, radius and also how to find the circumference of a circle using a cookie as an example. When you draw a line against the cookie passing through its center and touching its boundaries, it is a diameter of the circle. Radius of a circle is half the diameter of the circle. The length of the circle along the border of the circle is called circumference of the circle. The formula to compute the circumference of a circle is 2 * Pi * r, where r is...
How To: Use the PRIME operator in math
In this video, we learn how to use the PRIME operator in math. The prime operator is the opposite of something in the equation. Take a look at the illustration in the video that is shown. Once you see that, you will be able to tell what A prime and B prime are. A prime is the opposite of "A". If a number is shaded in "A" it should not be shaded in "A Prime". The same goes for the prime of the letter "B". Just pay attention to what the numbers selected for each letter is, then use the opposite...
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: Solve multi-step inequalities
In this tutorial the instructor shows how to solve multi-step inequalities. He explains the first rule of solving inequalities, stating that when you divide both sides by a negative sign, the inequality of the equations changes to the opposite. He goes on and explains this rule by solving a small inequalities equation and arriving at the result. So if you are looking to learn how to solve inequalities, follow the procedure given in this tutorial.
How To: Use the Chain Rule for finding derivatives
JustMathTutoring This video shows the procedure of finding derivatives using the Chain Rule. The Chain Rule states that the derivative of a composition of functions is the derivative of the outside function evaluated at the inside multiplied by the derivative of the inside. This can be stated as if h(x) = f[g(x)] then h'(x)=f'[g(x)]g'(x). This is explained by two examples. In the first example we find the derivative of the sine of square of 'x'. We take the derivative of sine at square of 'x'...
How To: Divide bigger numbers
In this video, we learn how to divide bigger numbers. As an example, let's say you were dividing 843 by 13. To make this easier, write down the times tables for 13 down and keep adding up. After you do this, see how many times 13 goes into 84. Your table will tell you how many times it goes into the larger number. Thirteen will go into 84 six times, so write six on the top line above the four, then subtract 78 from 84 and write a 6 next to the 4. Now, work out the remainder and when finished,...
How To: Find the point slope form of a line equation
This is a mathematical instructional video on finding the point slope form of a line equation. This technique allows you to find the x and y intercepts of a line. The point slope form is (y-y1)=m(x-x1). The instructor tells you what each of the variables represents, and shows an example. He then shows you how to find the slope-intercept form from the point slope form. Finally, he shows you how to graph the line using both of the equations. He shows you how to find the equations with different...
How To: Solve a quadratic equation with the quadratic formula
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 solve quadratic equations by applying the quadratic formula.
How To: Find limits with L'Hôpital's (Bernoulli's) rule
Need to evaluate limits involving indefinite forms? See how it's done with this free video calculus 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 pedagogical superstar Salman Khan's series...
How To: Graph linear inequalities
Solving the Inequalities using graph, first you have to take the inequality equation into equal. Then convert the equation into straight line equation i-e(y=mx+c). Giving own values for 'x' like (-1, 0, 1) we would get the value for 'y'. By plotting these points in the graph, you will get an straight line. If the given equation is greater than symbol, shade towards the positive part. If the given equation is smaller than symbol, shade towards the negative part. This is an one method to solvin...
How To: Use number patterns in math
In this video the instructor shows how to identify patterns in numbers, figures, letters. When given a pattern like 1, 2, 4, 7 try to find the change in each of the successive numbers in the pattern. If you observe carefully you will notice that the difference of the second and first number is one. Similarly the difference of the third and second number is two and this pattern keeps repeating. So this pattern is generated by taking 1 and adding 1 to it. To the next number add 2 to get the thi...
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: 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: Use interval notation to express inequalities
Could you use a little help figuring out how to use interval notation to express inequalties? Watch 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). With this free math tutorial, you'll learn how to give inequalities in interval nota...
How To: Factor a trinomial with negative leading coefficient
In this video the instructor shows how to factor a trinomial with negative leading coefficient. Most of the students are confused when they have to factor a trinomial with a negative leading coefficient. But there are many ways to solve these kind of problems as shown in this video. One way you can do is that take out the greatest common factor (GCF) of -1 from the equation. So pulling the -1 gives you the original trinomial with all the signs of the terms changed. Now go on and factor the ne...
How To: Use the upside-down birthday cake method to find a GCF
Need to find the greatest common factor for a set of numbers? Easy as cake. Learn how to find GCFs using the upside-down birthday cake method 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 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 word problems involving domain and range
See how to find the domain and range of a function implied by a word problem 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). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutor...
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: 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: 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: 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: Bisect a line segment
In this tutorial, we learn how to bisect a line segment. First, you need to adjust your compass so the distance from the sharp part and the drawing part is the size of the line. Then, put the sharp part on one side and draw your arc with the pencil. Do this on both sides of the line so your image shows two arcs that intersect each other. Since you have these two intersecting lines, you can draw a line between these to show where the middle of the line would be. Use a ruler to draw this straig...
How To: Find the percentage of a number
In this tutorial the author explains of how to compute percentages of a given number. He explains that x percent of some number y is x multiplied by y and divided by 100. He says that of means multiply and percentage means for hundred. He goes on and explains this concept with numerous examples. He suggests a small trick to move the decimal point of a number two digits to the left to get it divided by hundred. The author demonstrates many more similar tricks and short cuts using which one can...
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 differential equations to represent growth
This video shows the method to use differential equations to represent growth. Consider the function y=multiple of C & e raised to kx or Ce^(kx). Differentiating it with respect to x, we get dy/dx=kCe^(kx) or ky. So, the solution of the differential equation dy/dx=ky is Ce^(kx). There are two possibilities in the function y=e^(kx). It can be exponentially growth or decay function. This depends on the value of k. If k is greater than 0 or k>0, we get an exponential growth function. On the othe...