Given a sequence, (an) = {1,2.5,4,5.5,7...}.
We have to find the common difference of the terms of the given sequence, if the common difference is same then, we can say that this is an AP.
[tex]a_2-a_1=2.5-1=1.5[/tex][tex]a_3-a_2=4-2.5=1.5[/tex][tex]a_4-a_3=5.5-4=1.5[/tex]
Here, the common difference is the same. Thus, the given sequence is an arithmetic sequence and the common difference is 1.5.
