Hi

I have taken the problem from "A friendly introduction to analysis:single and multivariable " second edition by Witold Kosmala. And the statement is

Suppose that $\displaystyle f:X\rightarrow Y$ Prove that

$\displaystyle f(\emptyset)=\emptyset$ where $\displaystyle \emptyset$ is an empty set.

Since both $\displaystyle f(\emptyset)=\emptyset$ and $\displaystyle \emptyset$ are sets, I am using

standard approach used to prove the equality of the sets. I have downloaded the

errata from the author's website at

Code:

http://www.mathsci.appstate.edu/~wak/

thanks