# Quick Function Question

1. Oct 13, 2007

### Swapnil

What is exactly the difference between $$f$$ and $$f(n)$$ and why can't we write $$(f \circ g)(n)$$ as $$f(n) \circ g(n)$$?

Last edited: Oct 13, 2007
2. Oct 13, 2007

### Eighty

f is the function, f(n) is the value of the function at the point n. The ball operator $$\circ$$ acts on functions, not values, so your second expression is wrong.

3. Oct 14, 2007

### d_leet

You can, however, write it as f(g(n)).

4. Oct 15, 2007

### hashimcom

u can write it
no proplem.........i thenk

Last edited by a moderator: Oct 15, 2007