Consider the arithmetic sequence presented in the table below.

n 5 71

an 74 1,460

Hint: an = a1 + d (n - 1), where a1 is the first term and d is the common difference.

Part A: What is the first term, a1, of the sequence?

Part B: What is the general term equation, an, for this sequence?

Part C: What is the value of the 13th term of this sequence?

Question

Mathematics

Stone

18 February, 18:45

Consider the arithmetic sequence presented in the table below.

n 5 71

an 74 1,460

Hint: an = a1 + d (n - 1), where a1 is the first term and d is the common difference.

Part A: What is the first term, a1, of the sequence?

Part B: What is the general term equation, an, for this sequence?

Part C: What is the value of the 13th term of this sequence?

+5

Answers (1)

Know the Answer?

Jaime Huff · Answer 1

A5 and a71 are 66 places apart

a71 = a5 + 66d

1460 = 74 + 66d

1460 - 74 = 66d

1386 = 66d

1386/66 = d

21 = d

a5 = a + (5-1) * 21

74 = a + 4 * 21

74 = a + 84

74 - 84 = a

-10 = a < = = = first term

general term equation : an = - 10 + (n-1) * 21

a13 = - 10 + (13 - 1) * 21

a13 = - 10 + 12*21

a13 = - 10 + 252

a13 = 242