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Which explicit function defines this arithmetic sequence?

-351, -343, -335, -327, -319

A.
f(n) = 8n − 351
B.
f(n) = -8n − 351
C.
f(n) = 8n − 359
D.
f(n) = -8n + 359

User Anil Talla
by
5.3k points

2 Answers

12 votes

Answer:A:f(n)=8n-359

Explanation:

User Tomi Aarnio
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1 vote

Answer:

C. f(n) = 8n − 359

Explanation:

The given arithmetic sequence has first term -351, and common difference (-343 -(-351)) = 8. The common difference will be the multiplier of n in the explicit function.

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You can identify the appropriate explicit function by finding the one that correctly describes the sequence. Evaluating each for n=1 is sufficient. (You will note that choices B and D have the wrong sign on the multiplier of n.)

A f(1) = 8 -351 = -343

B f(1) = -8 -351 = -359

C f(1) = 8 -359 = -351 . . . . correctly gives the first term

D f(1) = -8 +359 = 351

The sequence is defined by the explicit function ...

f(n) = 8n -359

User Kasta
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