Question

Let $X=\{1,2,3,4,5\},Y=\{1,3,5,7,9\}$ and a relation from $X$ to $Y$ is defined as $\left\{\right(1,1),(1,3),(3,5),(3,7),(5,7\left)\right\}$. Verify whether the relation is a function or not. If not, give reasons.

Answer 1

As per definition, a function is a relation in which each input will have only one output.

Here, inputs 1 and 3 in X have multiple outputs in Y and hence cannot be classified as a function.