For this case we first define the variable: x = number of terms. The equation that models the problem is: f (x) = 3.4 - 0.6x We have then that the first four terms are: x = 1 f (1) = 3.4 - 0.6 (1) = 3.4 - 0.6 = 2.8 x = 2 f (2) = 3.4 - 0.6 (2) = 3.4 - 1.2 = 2.2 x = 3 f (3) = 3.4 - 0.6 (3) = 3.4 - 1.8 = 1.6 x = 4 f (4) = 3.4 - 0.6 (4) = 3.4 - 2.4 = 1 Answer: The rule for the sequence is: f (x) = 3.4 - 0.6x option 1
F(1)=2.8, f(2)=2.2, f(3)=1.6, f(4)=1 f(2)-f(1)=2.2-2.8=-0.6 f(3)-f(2)=1.6-2.2=-0.6 f(4)-f(3)=1-1.6=-0.6 Then the function decreases 0.6 units by each unit increases x: Options 1 or 2
With the first function: x=1→f(1)=3.4-0.6(1)=3.4-0.6→f(1)=2.8 OK
With the second function: x=1→f(1)=2.8-0.6(1)=2.8-0.6→f(1)=2.2 NO
