Respuesta :

The explicit formula is tn = -1/3 + 2/3(n - 1) and the value of t20 is 37/3

How to determine the explicit formula?

The terms of the sequence are given as:

t2 = 1/3

t8 = 13/3

An arithmetic sequence is represented as:

tn = a + (n - 1)d

So, we have:

t2 = a + d

t8 = a + 7d

This implies that

a + d = 1/3

a + 7d = 13/3

Subtract the equations

6d = 12/3

Solve for d

d = 2/3

Substitute d = 2/3 in a + d = 1/3

a + 2/3 = 1/3

Solve for a

a = -1/3

Substitute d = 2/3 and a = -1/3 in tn = a + (n - 1)d

tn = -1/3 + 2/3(n - 1)

Hence, the explicit formula is tn = -1/3 + 2/3(n - 1)

The value of t20

This means that n = 20.

So, we have:

t20 = -1/3 + 2/3(20 - 1)

Evaluate

t20 = 37/3

Hence, the value of t20 is 37/3

Read more about arithmetic sequence at:

https://brainly.com/question/6561461

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