Functions??

There is no need to study functions, per se. There is, however, a category of strange problems called "defined functions". Typically, ETS will define a function using a strange symbol.

For example:

Suppose x##y = (x + y)/y. What is (4##5)##2?

The trick is to simply follow directions carefully and make sure you add the appropriate assumed parentheses.

The more difficult type of these problem are like this:

Suppose x##y = (x + y)/y. Is the ## operation associative? (i.e., is (a##b)##c = a##(b##c)?

Be careful. Sometimes they use the same variables in the implementation as the ones that they use in the definition of the problem. Remember, the variables in the DEFINITION of the functions are merely placeholders. To avoid confusion, simple change the variables in either the definition or the implementation of the defined function so that they are mutually unique.

Hope this helps.