Question

What is the sum of the first 10 terms of the sequence defined by an = 3n - 3?

Answer 1

term1= 3(1) - 3 = 0
term2 = 3(2) - 3 = 3
term3( = 3(3) - 3 = 6
....
looks like an arithmetic sequence , with a=0 and d = 3
sum(1) = (10/2)(2(0) + 9(3))
= 5(27) = 135