A sequence is defined by the recursive function [tex]f(n+1) = -10 f(n)[/tex].

If [tex]f(1) = 1[/tex], what is [tex]f(3)[/tex]?

A. 3
B. [tex]-30[/tex]
C. 100
D. [tex]-1,000[/tex]



Answer :

Given the sequence defined by the recursive function [tex]\( f(n+1) = -10 f(n) \)[/tex] where [tex]\( f(1) = 1 \)[/tex], we aim to determine the value of [tex]\( f(3) \)[/tex].

Let's analyze the sequence step by step:

1. Initial Value:
The initial value given is [tex]\( f(1) = 1 \)[/tex].

2. First Recursion:
To find [tex]\( f(2) \)[/tex], we use the recursive definition:
[tex]\[ f(2) = -10 f(1) \][/tex]
Substituting [tex]\( f(1) \)[/tex]:
[tex]\[ f(2) = -10 \times 1 = -10 \][/tex]

3. Second Recursion:
To find [tex]\( f(3) \)[/tex], we again use the recursive definition:
[tex]\[ f(3) = -10 f(2) \][/tex]
Substituting [tex]\( f(2) \)[/tex]:
[tex]\[ f(3) = -10 \times (-10) = 100 \][/tex]

Through this process, we established that:
[tex]\[ f(1) = 1, \quad f(2) = -10, \quad f(3) = 100 \][/tex]

Thus, the value of [tex]\( f(3) \)[/tex] is:
[tex]\[ \boxed{100} \][/tex]