The isFactorised method checks that a mathematical expression is in factorised form. It can handle polynomials up to degree 2, with a single variable.

For example, if you set 3(x+2) as the the Value with equivSymbolic then add the isFactorised method, a learner would be marked incorrect for 3x + 6, as that expression is not factorised.

isFactorised doesn’t take any value which means when used alone it will validate any mathematical expression presented in its factorised form. For example, 3, x, (x-2), (x+3)(4-5) and so on would all be marked as correct if only using isFactorised.

IsFactorised is generally used as a supporting method in conjunction with equivSymbolic.

In this example, we use isFactorised with equivSymbolic. The whole expression is entered into the equivSymbolic Value field to ensure learners' responses are factorised and also match the expression.

In the image below we can see that x(x-3) + 2 - although equivalent to x^2-3x+2 - has been marked incorrect as it is not fully factorised. (x-2)(x-1) and (x-1)(x-2) have both been marked as correct as the order does not matter for this task.

In this example, we use the same approach as above, but set the Field for isFactorised to Complex numbers.

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.