Quest of Nine

The Book

Functions

Functions change a number using mathematical operators ( like +, - x and ÷ ) and other numbers.

e.g. a simple function of +5 changes:

3 to 8(3 + 5 = 8)
8 to 11 (8 + 5 = 11)
0 to 5 (0 + 5 = 5)
-5 to 0 (-5 + 5 = 0)
-8 to - 3 (-8 + 5 = -3)

a simple function of x3 changes:

3 to 15(5 x 3 = 15)
8 to 24 (8 x 3 = 24)
0 to 0 (0 x 3 = 0)
-5 to -15 (-5 x 3 = -15)
-8 to - 24 (-8 x 3 = -24)

One way to show this is as a diagram

inputfunctionoutput
3arrow+5arrow8
-5arrowx3arrow-15

Can you work out what the output of these functions will be?

inputfunctionoutput
3arrow+100arrow?
6arrowx6arrow?
9arrow-20arrow?
12arrow÷4arrow?
-4arrow+50arrow?
-2arrow-20arrow?