For those who do not use the computer often, it may be difficult to use the keyboard, as some things we do by writing by hand, with the keyboard are slightly different.

A very common case, which I imagine is strange to non-experts, are the **mathematical symbols**. How can I write 10 times 10 equal to 100? and 100 divided by 10 equal to 10?

## The number 0 (zero) or the letter “o”

First we learn to recognize the symbol of the number “zero” or “**0**“, which is not to be confused with the letter “**o**“. Note that the zero is usually recognized as it is high and narrow, while the letter “**o**” is low and wide.

## Addition / the “plus”

The “plus” is obtained through a single button, no special combination is needed.

There are two possibilities:

1) next to the enter key: the + symbol can be seen in the lower left corner, or

2) if you have the full keyboard via the numeric keypad, usually the larger key above the send

## Subtraction / the “minus”

The “minus” is obtained through a single button, no special combination is needed.

There are two possibilities:

1) near the shift key, above the ctrl, to the right of the space bar, or

2) if you have the full keyboard via the numeric keypad, it is usually found at the top, above the plus (+)

## The multiplication / the “per” / the “x”

First of all we must know that the **multiplication**, accustomed to using “on paper” the symbol of the letter “x”, with the computer must be replaced with the symbol of the “star”, that is “*****“.

You can find the symbol easily in the numeric keypad (right part of the keyboard) if you have a “normal” keyboard, instead if you have a laptop with a reduced keyboard, you can find it in the right part. So to get the “*****” you have to press the “**uppercase**” key and at the same time the “**+**” key.

Other more advanced mathematical symbols such as Alpha, Beta, Delta, Gamma, Omega, PI, Phi, and so on, you can get them with the character map. A detailed explanation can be found in this other article of mine, which explains how to get all the symbols with the keyboard.

## The division, the symbol “/”

As for the **division**, which on paper we usually represent with the colon “:”, the symbol of the “bar” or “**/**” must instead be used with the computer.

Pay attention that there are two different bars (“**/**” called “slash” and “**\**” which we can call “backslash”). The division symbol can be found near the ” *****” on the numeric keypad, or above the “**7**” key. You will then have to press the “**uppercase**” key and at the same time the “**+**” key.

## Exponentiation

As for the **exponentiation**, which on paper we usually represent with a small number at the top right of the number (technically called a superscript), the symbol “**^**” must be used with the computer. Unlike the others you will not find it on the numeric keypad, but close to the Enter/new line key. Then you will have to press the “** uppercase**” key and at the same time with another key.

## The other operations

Instead for “**> greater than**“, “**< less than**“, “**+**” and “**–**” the same symbols remain.

For other operations there is no specific key, but you will have to use the **calculator features**, or use **special programs**, as for example to write the equations in the same way we are used to writing them on paper. An example is to use **Microsoft Word** and the specific integrated tool called “**Equation**“.

## To summarize

- multiplication: 10 * 10 = 100
- division: 100/10 = 10
- exponentiation: 10 ^ 2 = 100
- addition: 10 + 10 = 20
- subtraction: 10 – 6 = 4
- 4 is greater than 2: 4 > 2
- 2 is less than 4: 2 < 4

## Advanced: formulas

In advanced chemical or mathematical formulas, two characters that are not exactly easy to obtain are used: the superscript and the subscript.

The superscript is the top number used in exponentiation, such as 10 ^{5}.

The subscript is the bottom number used in chemical formulas, such as H_{2}O.

To get them the best is to use a program like “Word” (or similar free, like LibreOffice Writer). There are special buttons in the “Font” section next to bold, italics, etc. You select the number – for example the “2” – and then you press one of these two buttons, you will immediately understand how it works!

If you want to get a “subscript” but the program you use does not support it (like the “Notepad” to understand each other) then you will have to use the “Character Map”, which as I explain in another article allows you to obtain any character that the Font that you use has available.