Use the recursive function for the geometric sequence 2,-6,18 and -54 to represent the 9th term
f(9)=f(8)•(-3)
f(9)=f(1)•(-3)^8
f(9)=f(1)+3(8)
f(9)=f(8)+3(8)

The first option is correct.

The following information should be considered:

Now

So,

the 9th term can be found using

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A

Step-by-step explanation:

A recursive formula allows the term in a sequence to be obtained from the previous term.

To find any term in the sequence multiply the previous term by the common ratio r

r = - 6 ÷ 2 = 18 ÷ - 6 = - 3

Thus the 9 th term can be found using

f(9) = f(8) × - 3 = - 3f(8) → A

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)