write a rule for the following functions.

Question

X -1 0 1 2 y 3/2 1 2/3 4/9

Answer 1

 x-values  y-values
     -1            3/2
      0              1
      1             2/3
      2              4/9
 
Notice that the x-values increase by 1 as you go from each to the next.
 
The y-values, however, decrease -- they are each (2/3) of the previous value.
 
We can express the rule as:    y_i+1 = (2/3)y_i             [Use this for a sequence]
 
or write it in terms of x:     y = (2/3)^x                     [use this for y is a function of x]

Answer 2

x: -1 0 1 2

x_i+1 = x_i + 1

 

y: 3/2 1 2/3 4/9

y_i+1 = y_i •2/3