If f(x)=x^2 and A={1,2,3} is the domain of f, which of the following is the graph of f on A?

Correct answer: {(1,1),(2,4),(3,9)}

The graph of a function is the set of all ordered pairs (x,f(x)). Here, f(1)=1^2=1, f(2)=2^2=4, and f(3)=3^2=9, so the graph is {(1,1),(2,4),(3,9)}. Option C represents the identity function y=x, while option B gives 6 instead of the correct value 9 for x=3. Exam tip: calculate f(x) for every element of the domain before forming the ordered pairs.