To begin, let's observe the given terms in the sequence to determine the value of the first term as well as the .
-1→+0.5-0.5→+0.50→+0.50.5
As we can see
d=0.5 and
a1=-1. We can use this information to write an equation for the
nth term of the sequence.
an=a1+(n−1)d
an=-1+(n−1)0.5
an=0.5n−1.5
We can calculate the fifth term of the sequence,
a5, by substituting
n=5 into our equation.
an=0.5n−1.5
a5=0.5(5)−1.5
a5=1
Graphing the Sequence
When graphing a sequence, the x-axis always represents the number of the term n and the y-axis represents the value of the term an.
n
|
0.5n−1.5
|
an
|
(n,an)
|
1
|
0.5(1)−1.5
|
-1
|
(1,-1)
|
2
|
0.5(2)−1.5
|
-0.5
|
(2,-0.5)
|
3
|
0.5(3)−1.5
|
0
|
(3,0)
|
4
|
0.5(4)−1.5
|
0.5
|
(4,0.5)
|
5
|
0.5(5)−1.5
|
1
|
(5,1)
|
Now let's graph these points on a coordinate plane.