1. INDICES

2. Squaring a Number • 32means ‘3 squared’, or 3 x 3. • The small 2 is an index number, or power. It tells us how many times we should multiply 3 by itself. • Similarly 72 means ‘7 squared’, or 7 x 7. • And 102 means ‘10 squared’, or 10 x 10. • So, 12 = 1 x 1 = 1 • 22= 2 x 2 = 4 • 32= 3 x 3 = 9 • etc. • 1, 4, 9, 16, 25… are known as square numbers.

3. Cubing a Number • 2 x 2 x 2 means ‘2 cubed’, and is written as 23. • 13= 1 x 1 x 1 = 1 • 23= 2 x 2 x 2 = 8 • 33= 3 x 3 x 3 = 27 • etc • 1, 8, 27, 64, 125… are known as cube numbers.

4. Index Laws Multiplying and Dividing: • When multiplying you add the indices, and when dividing you subtract the indices. Adding and Subtracting • You can only add and subtract ‘like items’. • Remember that if we have a mix of terms we must gather like terms before we simplify.

5. Using a Calculator • A calculator can be used to work out one number to the power of another. • The index button is usually marked xy or yx. • Sometimes you need to press SHIFT or 2ndF to use this buttonFor example, to calculate 54, you may need to press • You should find out which buttons you need to use on your calculator.Make sure that you get the correct answer of 625 for the calculation above.