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Consider the arithmetic sequence 3,8,13,18 find S15

User Hoots
by
7.2k points

1 Answer

5 votes

Answer:

This is an arithmetic sequence since there is a common difference between each term. In this case, adding

5

to the previous term in the sequence gives the next term. In other words,

a

n

=

a

1

+

d

(

n

1

)

.

Arithmetic Sequence:

d

=

5

This is the formula of an arithmetic sequence.

a

n

=

a

1

+

d

(

n

1

)

Substitute in the values of

a

1

=

3

and

d

=

5

.

a

n

=

3

+

(

5

)

(

n

1

)

Simplify each term.

Tap for more steps...

a

n

=

3

+

5

n

5

Subtract

5

from

3

.

a

n

=

5

n

2

Explanation:

User Mohammad Salehi
by
8.9k points