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Interval
Consider the case that the answer to a problem is an interval or an union of disjoint intervals.
The optional TeX command \allowIntervalUnionsForInput[true]
enables the option that the student's answer can be given by the union of multiple intervals.
Solution syntax
The solution is defined by a left and a right boundary , both seperated by a semicolon.

symbol 
open left boundary 
( or ] 
closed left boundary 
[ 
open right boundary 
) or [ 
closed right boundary 
] 
e.g. \solution{(1;1]}
, \solution{]1;1]}
(same interval as the first one), \solution{(myVar;100[}
The correct solution as an union of multiple disjoint intervals can be given by separating them with a comma. E.g. \solution{(infinity;2],[3;infinity)}
Be aware that this is only possible if the optional command \allowIntervalUnionsForInput[true]
is used.
Examples
1 2 3 4 5 6 7 8 9 10  \begin{question}
\text{Write down the interval from 1 to 3:}
\type{input.interval}
\begin{answer}
\text{ A = }
\solution{[1;3]}
\end{answer}
\end{question}

1 2 3 4 5 6 7 8 9  \begin{question}
\begin{answer}
\text{input.interval: $[1;4) = $}
\allowIntervalUnionsForInput
\solution{[1;4)}
\end{answer}
\end{question}

More Examples
Multiple of π as interval boundaries
If you want that the solution and/or the answer boundaries can be written as multiple of π use the command \allowForInput{pi}
.
Example
1 2 3 4 5  \begin{answer}
\text{input.interval: $[\pi;4\cdot\pi) = $}
\allowForInput{pi}
\solution{[pi;4*pi)}
\end{answer}
