Understanding Functions Worksheet

Sample problems

A function assigns exactly one output to each input. Decide whether each relation is a function, evaluate functions at given inputs, and read input/output tables.

1. 1. Does the set of ordered pairs $\{(1,3),(2,5),(3,7),(4,9)\}$ represent a function? Explain.
2. 2. Does the set $\{(2,4),(3,6),(2,8),(5,10)\}$ represent a function? Explain.
3. 3. Which mapping represents a function?
   • $1\to a,1\to b,2\to c$
   • $1\to a,2\to a,3\to b$
   • $2\to a,2\to b,3\to c$
   • $4\to a,4\to b$
4. 4. The function is given by $f(x)=3x+2$. Find $f(4)$.

Plus 10 more problems and a full answer key in the PDF.