Given the formula for an arithmetic sequence f (9) = f (8) + 4 written using a recursive formula, write the sequence using an arithmetic explicit formula.

f (9) = f (1) + 1

f (9) = f (1) + 4

f (9) = f (1) + 8

f (9) = f (1) + 32

The answer is option d

Step-by-step explanation:

The given formula is for arithmetic sequence is

f (9) = f (8) + 4

By using the formula an = a + (n-1) d

Where a is the first term and d is the common difference and n is the nth

term

∵ By substituting in the main equation we get

a + 8d = a + 7d + 4

d = 4

So by analyzing the options we get answer as option d

f (9) = f (1) + 32

a + 8d = a + 32

8*d = 32

8*4 = 32

32 = 32

∴The answer is option d