Variables using
input output
1 -> 3
2 -> 5
3 -> 9
4 -> 17
5 -> 33
How do you get the answer?
To solve it we must be clever enough to observe
a pattern.
Notice by looking at the row of five numbers:
3, 5, 9, 17, 33
that they are respectively 1 more than this
row of five numbers:
2, 4, 8, 16, 32
If we are clever enough, we can recognize the
row of five numbers above as the successive
powers of 2:
21, 22, 23, 24, 25
So the rule for the function is
"Take the input number, raise 2 to that power, add one
to that and the number you get will be the output number."
If each input is represented by a value of x and
each output is represented by a value of y, then
y = 2x + 1
This can also be represented by f(x) instead of y, like
this
f(x) = 2x + 1
Edwin
