# Domain restrictions

In the solving equation tasks of the Algebra interaction type, you can enter domain restrictions to describe the set of values for which the answer is defined. Currently, domain restrictions only work for numerical ranges.

In AlgebraKiT, you can write your domain restrictions in the form of an inequality using the variable which the original equation in the task is solved to.

##### Examples

Some typical examples of domain restrictions when solving an equation are:
$x>0$
$0 \le x \le 5$
$-1 < x < 1$
$n^2 > 4$

It is currently not supported to write domain restrictions in other variables than the variable you are solving to.

For example, the solution set of an equation with a solution $x=2a$ or $x=-2a$ can not be restricted by using domain restrictions such as $x>a$ or $x>0$ to filter the negative variant.

Units

In case (the solution of your) equation contains units, the domain restrictions also have to be defined including these units.

##### Examples

Some typical examples of domains with units are:
$x>0m$ for unit meter
$0m \le x \le 5m$ for unit meter
$-\pi < x < \pi$ for radian units
$0\degree \le x \le 360\degree$ for gonio degree units