# Videos

Choose from over 80 mathematical videos.

Our team of top teacher mathematicians have put together all the important topics and explain them with the types of examples that you would find in a normal textbook or exam.
• #### Properties of straight line segments

Properties of straight line segments. In this unit a system of co-ordinates is described, and is used to find various properties of the straight line between two points. The distance between the two points and the mid-point of the line joining the two points are calculated.
Length: 27 minutes
• #### Pythagoras' Theorem

Pythagoras' theorem. Pythagoras' theorem - the square on the hypotenuse is equal to the sum of the squares on the other two sides - is well known. In this tutorial we revise the theorem and use it to solve problems in right-angled triangles. A less familiar form of the theorem is also considered.
Length: 26 minutes

Radian measure . Most people usually learn to measure an angle in degrees. But in many scientific and engineering calculations radians are used in preference to degrees.
Length: 24 minutes
• #### Ratios

A ratio is a way of comparing two or more similar quantities, by writing two or more numbers separated by colons. The numbers should be whole numbers, and should not include units. This video shows how to approach ratio problems.
Length: 25 minutes
• #### Rules of arithmetic

If a mathematical expression is complicated, it may not be clear which part of it should be evaluated first, and so some rules have been established. There are also rules for calculating with negative numbers. This video covers the rules of precedence, adding, subtracting, multiplying and dividing negative numbers.
Length: 30 minutes
• #### Sigma notation

Sigma notation. Sigma notation is a method used to write out a long sum in a concise way. In this unit rules for using sigma notation are established.
Length: 27 minutes
• #### Simple Linear Equations

This video gives examples of simple linear equations and shows how the unknown quantity can be found. This involves collecting terms, removing brackets, and solving linear equations with fractions.
Length: 33 minutes
• #### Simplifying Algebraic Fractions

This involves simplifying fractions to their lowest equivalent form, fractions that need to be factorised before simplifying and looks at common mistakes made when cancelling.
Length: 18 minutes
• #### Simultaneous Linear Equations

Solving a pair of simultaneous equations is equivalent to finding the location of the point of intersection of two straight lines This video looks at the main methods of solving simultaneous linear equations - elimination, substitution and then looks at further examples and how to approach them.
Length: 34 minutes
• #### Solving Cubic Equations

Cubic equations have either one real root, or three real roots. In this video we explore why this is so, how to solve them to find the roots and how to use graphs to solve them.
Length: 21 minutes