Answer variants:
\(f(\)\(d\)\()\) \(=\) \(9\)
\(f(\)\(d\)\()\) \(=\) \(4\)\(c\) \(+\) \(5\)
\(f(\)\(d\)\()\) \(=\) \(d\)
Sort the functions into their types.
 
Column A
Column B
Real-valued function
 
Constant function
 
Identity function