# Duplicate symbol definitions

When authoring an exercise, it might be the case that you want to use the multiple definitions of the same symbol next to each other in the exercise.

Let us look at an example using the physics formula $W=m \times g$ where $W$ is the weight, $m$ the mass of the object, and $g$ gravitational acceleration.

In the above exercise, the symbols $m$ and $g$ are used with multiple definitions:

• $m$ for the variable representing mass and the unit meter
• $g$ for the variable representing gravity and the unit gram

Although the unit gram might not be directly used in the exercise definition, it is included in the context, since the unit $kg$ is used, and thus AlgebraKiT automatically derives that $g$ might also be used as a unit of weight.

For both symbols, we can define that they have multiple definitions, such that AlgebraKiT understands the exercise definition and is able to generate the worked solution and process student input automatically.

To enable this functionality, go to the Symbols tab at the top of the exercise, and add your symbol (in our example $m$) as a multiple. Next, add the required entries. In our example, one for unit, and one for variable. Give your entries a name. For example:

You can now author the question as you intended, except you have to use the names you just created to refer to the specific symbol. So in our example, we use $mUnit$ to refer to the unit meter and $mVar$ to refer to the variable $m$ for mass.

The student can still write $m$ to refer to both inputs, and AlgebraKiT will match which of the two $m$ definitions is intended.

The same applies for symbol $g$, which is left as an exercise for the reader (or refer to this AlgebraKiT Library example where the question is available for your reference).