Question

For each sequence, find the first 4 terms and the 10th term.
A) n+5
B)2n-1

Answer 1

see explanation

Explanation:

(a)

To find the first 4 terms substitute n = 1, 2, 3, 4 into the n th term formula.

a₁ = 1 + 5 = 6

a₂ = 2 + 5 = 7

a₃ = 3 + 5 = 8

a₄ = 4 + 5 = 9

For the 10 th term substitute n = 10, that is

a₁₀ = 10 + 5 = 15

The first 4 terms are 6, 7, 8, 9 and the 10 th term is 15

(b)

Substitute n = 1, 2, 3, 4 and 10 into the n th term formula

a₁ = 2(1) - 1 = 2 - 1 = 1

a₂ = 2(2) - 1 = 4 - 1 = 3

a₃ = 2(3) - 1 = 6 - 1 = 5

a₄ = 2(4) - 1 = 8 - 1 = 7

a₁₀ = 2(10) - 1 = 20 - 1 = 19

The first 4 terms are 1, 3, 5, 7 and the 10 th term is 19