# Function machine problem

1. Aug 18, 2006

### nonstop

If we have function machine, which change numbers 1,2,4 and 7 like this

1 --> 4
2 --> 8
4 --> 16
7 --> 28

How i know simple, what is function, what machine use?

( I don't speak very well english )

2. Aug 18, 2006

### Staff: Mentor

From a numerical perspective, it looks like a straightforward scaling of the input number to get the output number (question -- what is the scale factor?).

From a binary state machine perspective, it looks like a shift left by a constant number of bits. How many bits?

3. Aug 20, 2006

### loom91

Machine? What are you talking about? Specifying a function at only 4 points does not specify the function, but for simple purposes you can consider the function to be a constant multiple of the input.

4. Aug 22, 2006

### murshid_islam

what did you mean by that question? can you please elaborate?

Last edited: Aug 22, 2006
5. Aug 22, 2006

### lo2

$$f(x)=4x$$

As:

$$f(1)=4 f(2)=8 f(4)=16 f(7)=28$$

6. Aug 23, 2006

### JonF

What lo2 said with a domain of {1,2,4,7}