How-tos

This demonstrates how to render a set of tuples such as $\{(1,2),(3,4)\}$ in LaTeX, starting with a list of pairs of numbers.

Shows how to enter a logarithm to an arbitrary base, in a mathematical expression part.

Ask for the squares of five randomly-chosen numbers between 0 and 15.

The shuffle function puts a list in random order.

A table showing how to substitute raw LaTeX code into question text.

NOTE: You probably don't want to do this! There's usually a more robust way, where you get Numbas to make the expression for you.

Demonstrates how to create variables containing LaTeX commands, and how to use them in the question text.

This question shows how to use the currency function to display amounts of currency with the correct symbols.

This question shows how to display a number like "1234" as "1,234", or "1 234", using the formatNumber function.

A method of randomly choosing variable names - use the expression() JME function to create a variable name from a randomly chosen string.

(This question also uses a custom marking script to check that the student has simplified the expression)

Demonstrating that \$ produces a normal dollar sign.

Use attributes of the form eval-<name> to dynamically set an attribute on an element based on question variables.

Use the CSS preamble to give a bit more space between multiple choice answers.

A randomised table is contained in a div tag with the id #sales-table, so it can be styled using the CSS preamble.

CSS classes "english" and "cymraeg" apply different background colours to English and Welsh portions of text.

Example of displaying a randomly chosen image.

There are copious comments in the definition of the function eqnline about the voodoo needed to have a JSXGraph diagram interact with the input box for a part.

The student is shown two number entry gaps on either side of a 'less than' sign. Their answer is marked correct if the first number is less than the second, using a custom marking algorithm.

This shows how to mark the gaps in a gap-fill part together, rather than independently.

A demonstration of how to use the "variable list of choices" option for a "choose one from a list" part to shuffle only some of the choices, and always have the same "I don't know" choice at the end of the list.

This question uses the linear algebra extension to generate a system of linear equations which can be solved.

We want to produce an equation of the form $\mathrm{A}\mathbf{x} = \mathbf{y}$, where $\mathrm{A}$ and $\mathbf{y}$ are given, and $\mathbf{x}$ is to be found by the student.

First, we generate a linearly independent set of vectors to form $\mathrm{A}$, then freely pick the value of $\mathbf{x}$, and calculate the corresponding $\mathbf{y}$.

To generate $\mathrm{A}$, we generate more vectors we need, then pick a linearly independent subset of those using the subset_with_dimension function.

The student's answer is a fraction of two polynomials. First check that the student's answer is a fraction, then check that the numerator is of the form $x+a$.

To find the script, look in the Scripts tab of part a.

An all-or-nothing marking scheme for a gap-fill part: the student must answer every gap correctly to get all the marks. If any gap is incorrect they get 0 marks for the whole part.

This question shows how to load a GeoGebra applet in JavaScript, avoiding the JME functions. This allows you to do some more complicated manipulation of the worksheet than simply redefining objects.

The student is asked to factorise a quadratic $x^2 + ax + b$. A custom marking script uses pattern matching to ensure that the student's answer is of the form $(x+a)(x+b)$, $(x+a)^2$, or $x(x+a)$.

To find the script, look in the Scripts tab of part a.

No description given

Choose from one of several pre-defined scenarios, and set variables to the corresponding values. 

This question has three variables: city, population, and percent_like_chocolate. These differ for each city. 

Display a number as a mixed fraction when appropriate, using the mixedFractions display option.

The custom function rectangle(width,height) draws a rectangle with the given dimensions, along with some labels.

Just showing how to use the stdev function from the stats extension to calculate the standard deviation of a list of numbers.

A function which renders the factorisation of a number in LaTeX.

Show a list of the factors of a number.

Works by testing each number up to $n$ for divisibility by $n$, so won't do well with really big numbers. Certainly fast enough for numbers up to 4 or 5 digits.

Some clever variable-substitution trickery to randomly pick two sides of a right-angled triangle to give to a student, and ask for the other.

The sides are set up so they're always Pythagorean triples, and the opposite side is always odd.

As ever, most of the tricky stuff is in the advice. 

Because this was created quickly to show how to set up the randomisation, there's no diagram. It would benefit greatly from a diagram.