An arithmetic sequence has a common difference.
Let's try if the given sequence has a common difference.
From the problem, we have :
[tex]\mleft\lbrace-9,-4,1,6,\ldots\mright\rbrace[/tex]The differences are :
[tex]\begin{gathered} -4-(-9)=5 \\ 1-(-4)=5 \\ 6-1=5 \end{gathered}[/tex]Since the differences are the same, the sequence is arithmetic.
The answer is Arithmetic Sequence
