4.1 Calculator exploration: exponents

Suppose you want to calculate 7 × 7 × 7 × 7. Do this on your calculator now; you should get 2401. This is fine, but as you have just seen, this calculation can be written more concisely as 7⁴ and there is a quicker way of calculating it, too.

To work out an exponent on a calculator, you use the buttons (x raised to the power y) or . Find the correct button on your calculator now.

If you are using a calculator on your phone you may need to change it to landscape mode in order for the button to be displayed.

On most calculators you will need to enter 7, then press the exponent key followed by the 4.

Try this now for 7⁴ and make sure you get 2401.

Most calculators will also have separate buttons for finding the square of a number and in some cases the cube. To find the square of a number, the button will look like and is just a short cut to finding this power; you need to press one less button!

So far you’ve been dealing with each operator separately in a calculation but there will be occasions where you will use them in combination. In these cases you will have to know the rule that is used to ensure that everybody gets the same answer to the same calculation. This will be the subject of the next section.