Question

Which expression describes the rule of this sequence?
3, 6, 9, 12, 15, 18
3 + (n – 1)
3n
3+ (3 x n)
3 + n

Answer 1

one option : you can plug values of n and check every one of them..
second and better option is to observe that this is an arithmetic sequence with a1 = 3 and d = 3

the general term in an arithmetic sequence is given by an = a1 + (n-1)*d
so what is the general term in this case ?