## BODMAS/BIDMAS on a calculator

**BODMAS** or **BIDMAS** must also be used when using a calculator. Scientific calculators automatically apply the operations in the correct order, however extra brackets may be required.

### Example

Consider this calculation:

If was entered on a calculator, the calculator would use BODMAS/BIDMAS and calculate . The division would be completed before the addition or subtraction. This would give the **wrong answer**.

To make sure the calculation is correct, use the **fraction button** on the calculator or use brackets:

or

## Calculating indices on a calculator

On a calculator, brackets must be used when raising negative numbers to a power.

For example, to calculate -2 squared on a calculator, type in . This would give the correct answer of 4. If brackets were not used, BODMAS/BIDMAS would be applied and the answer given would be -4, as the power is applied before the subtraction.

### Example

Find the value of when .

Using BODMAS/BIDMAS, the answer is calculated as:

- (power/indices first)
- (addition)

On a calculator, typing gives an answer of -2 as the calculator does not automatically understand that the minus sign relates to a negative number, rather than a subtraction.

To get the correct answer, include extra brackets. Typing into a calculator gives an answer of 16, which is correct.

When using calculators, place brackets around negative numbers before raising them to a power.