The equivLiteral method checks if the response from the learner is literally equal to the correct value set by the Author. This means that the learner needs to put in **exactly the same form, order, elements, and values**.

Use equivLiteral when you want to strictly specify a particular form of the mathematical expression as the correct answer.

**Note:** equivLiteral ignores parentheses (), by default.

# Examples using equivLiteral

## Example 1: Basic equivLiteral

In the example below, we've set all the responses with the same correct value and selected **Ignore order**.

In the image below we can see that 2² × 5² is marked correct because we selected **Ignore order**. However, 2 × 2 × 5 × 5 is in a different form so is marked incorrect.

## Example 2: Non-variable expressions

In this example, we can see that even though 0.5, 3/6 and 1/2 are mathematically equivalent (all one half), learners have to put their answer in the form we have set, ½, to be marked correct.

## Example 3: Variable expressions

In this example we can see that selecting **Ignore order** (as in Example 1) allows us to have the brackets in any order.

## Example 4: Excluding possible correct responses

In this example, the flexible equivSymbolic scoring rules are constrained by a supporting equivLiteral method,. Using equivSymbolic allows correct responses in various formats, and adding equivLiteral with **Inverse result** enabled ensures that learners will not be marked correct for the exact same expression as the one in the question stimulus. Now, any symbolically equivalent equation will be correct **except **for the value the author has set.

In the example below you can see that x² - 4 has been marked as incorrect.

# Additional options for the equivLiteral marking method

## Allow decimal marks

Authors can specify what separators learners can use. From the Thousand Separator drop-down menu, you can select dot, comma, and/or space. The Decimal Separator menu contains the option for either a dot or a comma.

**Note:** **Allow decimal marks** has to be selected for these options to show and that the specified thousand separators and decimal separator cannot be the same, e.g. both dot.

## Ignore order

Ignores the order of expressions. E.g. both x+1 and 1+x will be considered correct. If this is not enabled, equivLiteral will not accept the correct response specified by the Author in a different order.

## Inverse result

Enabling this means that the value specified in the Value field will not be accepted as the correct answer. It is a useful way of excluding very specific answers from validation.

## Allow interval

This option must be enabled when the learners are expected to insert interval notation in the response area, ie ‘[1, 4)’. Otherwise, the response will not validate correctly.

## Ignore trailing zeros

This option allows equivLiteral to ignore zeros after decimal separators in learners' responses. For example, when this option is enabled, 1000 and 1000.000 will be treated as equal.

## Ignore coefficient of 1

When enabled, the coefficient of 1 before an integer will be ignored. E.g. equivLiteral will treat 1x+2 and x+2 as equal.

## Treat 'e' as Euler's number

This option treats the variable 'e' as Euler's number. This overrides the default interpretation of 'e' as scientific notation.

## Compare Grouping

Enable this flag when using parentheses grouping with the equivLiteral method. This flag forces equivLiteral away from its default state to recognise parentheses and correctly support the commutative property of multiplication.