Equations

The online assessment tool requires that you type out your answers. This requires some adjustments to the format in which you structure equations and potentially the keyboard characters that are used to represent the various operators and symbols as compared to the hand written exam and how they are displayed in the learning material.

This lesson will detail the basic arithmetic operators, notation styles and symbols that can all be used on a standard keyboard to represent any of the equations you might reasonably be expected to type out.

Arithmetic operators

+ Addition e.g. 4 + 5 = 9

- Subtraction e.g. 7 - 3 = 5

x Multiplication e.g. 10 x 5 = 50

/ Division e.g. 6 / 2 = 3

: The ratio of two quantities e.g. 20 : 1

sqrt() Square root e.g. sqrt(16) = 4

^ exponentiation or superscript e.g. 4^2 = 16 or 42 = 16

Equality, similarity and comparison

= Equals 

> Greater than

>= Greater than or equal to

< Less than

<= Less than or equal to

∝ or ~ proportional to

Brackets

( ) Brackets should be used to segregate parts of your equation. 

(5 + 6) x 2 = 22

[ ] Square brackets and { } braces should be used for readability where nested brackets are required.

([3 + 7] x 2 / [3 + 1])   = 5

Common symbols

There are many symbols you will be familiar with from your studies that are used by convention in certain equations. These are often Greek letters, but may also be letters in the Latin alphabet which is used to write many languages, including modern English.

The online assessment tool will allow you to insert Greek symbols in your answers, or you may use any easily recognised alternative that can be typed on a standard keyboard. Some of these are suggested below. Please note that any particular symbol does not have any intrinsic value itself and they are used to represent certain values and properties by convention only. Indeed, many symbols and letters are used to represent completely different things in different equations. The most important thing is that you state the designation of any symbols or letters that you use at the top of your workings so that the examiner knows exactly what you intend them to represent. 

Some of the common symbols that you may be required to use, and their alternatives are given below. 

The value of Pi may be written "Pi" or the Greek symbol "π".

The difference between two values can be symbolised by the Greek letter delta "Δ" or the letter "d".

Example, ΔP or dP can be used for "difference in pressure".

Density may be represented by the Greek letter rho "ρ" or the letter "p".

Example, ρ = m / V or p = m / V where m = mass and V = volume.

Micro can be represented by the Greek letter mu "μ" or "u". 

Example, micrometre μm or um.