it is 8.
5
4,8,12,16,20
2
5, 11, 17, 23, 29
a1=2 d=3 an=a1+(n-1)d i.e. 2,5,8,11,14,17....
They are 14, 42, 126, 378 and 1134.
20, 15, 10, 5, 0, -5, -10, -15, -20 and so on.
37
The sum of the terms in a sequence is called a series. Sequence is a function whose domain is the natural numbers. So f(1)= first entry in the sequence, and f(2) is the next.... f(n) is the nth term. We usually don't write sequences that way. Instead of f(1) we write, a1 to refer to the first term. The function tells us the rule we use to find the terms of the sequence. So for example, f says take n and square it. Then the first 3 terms of the sequence are 1, 4 and 9 and the first 3 terms of the series are 1, 5 and 14
nth term is 8 - n. an = 8 - n, so the sequence is {7, 6, 5, 4, 3, 2,...} (this is a decreasing sequence since the successor term is smaller than the nth term). So, the sum of first six terms of the sequence is 27.
5
1, 1, 2, 3, 5, 8, 13, 21, ...Restate the question: What are the terms of the Fibonacci sequence?The Fibonacci sequence is formed by beginning with the first two terms both equal to one. From there on, each term is found by adding the two previous terms:1+1=2, 1+2=3, 2+3=5, 3+5=8, 5+8=13, 8+13=21, ...