Question

What is the arithmetic sequence of -8, -3 2, 7?

Answer 1

`a_(n)` = 5n - 13

Explanation:

The n th term (explicit formula) of an arithmetic sequence is

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = - 8 and d = - 3 - (- 8) = - 3 + 8 = 5. thus

`a_(n)` = - 8 + 5(n - 1) = - 8 + 5n - 5 = 5n - 13

Answer 2

a_n = -8 + (n - 1)5

Explanation:

a_n = a + (n - 1)d

a = first term = -8

n = number of terms

d = common difference = second term - first term = -3 - (-8) = -3 + 8 = 5

therefore

a_n = -8 + (n - 1)5