We are to determin if the following sequence are arithmetic and also fin their common difference if they are arithmetic.
(1) -3, -9, -27, -81, ................
This sequence is not an arithmetic sequence because theere is no common difference.
-9 - -3 = -27 - -9
-9 + 3 = -27 + 9
-6 ≠ -18
Therefore is not an arithmetic sequcence.
(2) 13, 17, 21, 25, ......................
This sequence is an arithmetic sequence.
It has a commdon difference of 4
17 - 13 = 21 - 17
4 = 4
Therefore, the sequence is an arithmetic sequence.
(3) -6, -2, 2, 6, .........................
This sequence is an arithmetic sequence.
It has a common difference of 4
-2 - -6 = 2 - -2
-2 + 6 = 2 + 2
4 = 4
Therefore, the sequence is an arithmetic sequence
