Question

What is the explicit formula of the arithmetic sequence?2, -2, -6, -10

Answer 1

We have the following sequence

`2,-2,-6,-10`

We calculate the pattern of change like this:

`\begin{gathered} -10-(-6)=-10+6=-4 \\ -6-(-2)=-6+2=-4 \\ -2-2=-4 \end{gathered}`

Therefore, by knowing the pattern of change, we can know the explicit formula

`a(n)=2-4(n-1)`