Deduce the expression, when the set of numbers {[[$ 0 $]], [[$ 1 $]], [[$ 2 $]], [[$ 3 $]], [[$ 4 $]]} is entered into the function machine and the output is

a) {[[$ 0 $]], [[$ 2 $]], [[$ 4 $]], [[$ 6 $]], [[$ 8 $]]}.



Answer: The expression is [[$ x $]] [[$ \rightarrow $]]

b) {[[$ 0 $]], [[$ \displaystyle\frac {1} {2} $]], [[$ 1 $]], [[$ 1 \displaystyle\frac {1} {2} $]], [[$ 2 $]]}



Answer: The expression is [[$ x $]] [[$ \rightarrow $]]

c) {[[$ -5 $]], [[$ -4 $]], [[$ -3 $]], [[$ -2 $]], [[$ -1 $]]}.



Answer: The expression is [[$ x $]] [[$ \rightarrow $]]