factorial calculator

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Factorial Calculator

What is factorial? How is it calculated? These are two major questions which students need to answer when they are dealing with this topic. In generic terms, if there is a number “n”, its factorial would be a product of all the numbers which have a value of less than or equal to “n”. Consider an example where the value of n is 4. Thus, its factorial would be given as.

\(\mathrm{As:}  n = 4 \) 
\( 4\times3\times2\times1 \)
\( n! = 24 \)

The use of a factorial calculator

Our factorial calculator stands out in every aspect. It is easy to use and the accuracy of results is not compromised in any manner. Here are the steps you have to perform to use this tool and determine factorial.

  1. Input and output for single number factorial
    To start with, enter the first number for which you have to calculate the factorial. Consider that you want to calculate the factorial of 6. Once you have entered the number, click the calculate button and you would see the output on the right side of
    the screen. In the outputs section, you would see two parts. The first would show you the answer. For instance, in this case, you are calculating the factorial of 6 so the answer would be 720. Now, a lot of people would want to see how the answer was calculated. This is where the second section comes into play. This part shows you how the answer was calculated. In this case, the value of 6! Is given as.

    \( 6\times5\times4\times3\times2\times1 = 720 \)
  2. The Advanced Option for factorial of multiple numbers
    When you click the tab titled “advanced factorial option”, a drop down menu would appear. This is where you have to provide information for the second number. First of all, select the mathematical operation which has to be performed. You can choose from subtraction, addition, division and multiplication. After that, enter the second number for which the operation has to be completed. Consider that it is “4” in this case. Along with that, let us reconsider the first number as 6 and opt for the subtraction option.
  • In mathematical terms, this option would be
    \(6! – 4! \)
  • Going through the outputs
    The outputs would be shown to you after you have clicked the “calculate” button. In the first row, the factorial of the first number and its calculation process would be shown. In this case, it would be 6! which carries a value or 720. The second portion would show how it was determined.

    \(6! = 6\times5\times4\times3\times2\times1 = 720 \)

    In the second row, the factorial of the second number would be shown along with its calculation process. In this example, the second number is 4. Thus, its factorial process would be

    \(4\times3\times2\times1 = 24\)

    The last row would show the result of the mathematical operation.
    In this case it would be \(6! – 4!\)

    The Factorial Formula and Example

    The formula of factorial has a simple logic behind it. For instance, consider that you have a number “b”, how would the factorial of this number be determined. It would be given as.

    \(b! = b (b-1) (b-2) … \)
  • If you have a look at the implementation of the formula, it explains that the factorial of a number is product of all the numbers that are less than or equal to it. Consider the following examples.

    \(10! = 10\times9\times8\times7\times6\times5\times4\times3\times2\times1\)
    \(10! = 3628800\)

    Similarly, if you want to determine the factorial of 8, the value would be

    \(8! = 40320\)


The factorial of zero and its calculations

Normally, people have a lot of confusion about what the factorial of zero is. Let us go through the example given below and understand by 0! Is equal to
Consider that you have a number “n” and its factorial has to be determined. The factorial would be given as.

\(n! = n(n-1)!\) , “this is the formula for calculating factorial”.

Consider that n = 1 and insert this value in the formula given above.

\((n-1)! = \dfrac{n!}{n}\)

\((1-1)! = \dfrac{1!}{1}\)

\(0! = 1\)


Analysis of results and formula used

If you have a glance at the formula mentioned above, the value of 0! Is 1. This series of calculations basically shows how the value of 0! can be determined. In other words, the core logic is explained through this example.

E Notation and its accuracy

The purpose of e notation is representing a number as a power of 10. Consider a proper example. If you have the number 120000, it can be represented as 1.2E5 or 1.2 X 10 to the power 5. In terms of accuracy, it does not have any problems. However, when you are using this format, you should try to perform the calculations in a careful manner.

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Dorothy Cunningham | 06/08/2019

Such an awesome work by developers. A very handy calculator.

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