Answer:
-1701
Step-by-step explanation:
The recursion relation tells you each term of the sequence is -3 times the previous term. Then the first 6 terms are ...
7, -21, 63, -189, 567, -1701
The value of f(6) is -1701.
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Additional comment
The explicit formula for a geometric sequence with first term 7 and common ratio -3 is ...
f(n) = 7×(-3)^(n-1)
Then f(6) is ...
f(6) = 7×(-3)^5 = 7×(-243) = -1701
