Answer:
6, 10, 8 is the correct answer.
Step-by-step explanation:
Given that, the recursive function:
[tex]a_n=a_{n-1}-(a_{n-2}-4)[/tex]
6th term, [tex]a_{6} =0[/tex]
5th term, [tex]a_{5} =-2[/tex]
To find:
First three terms of the sequence = ?
Solution:
Putting n = 6 in the recursive function:
[tex]a_6=a_{5}-(a_{4}-4)\\\Rightarrow 0=-2-(a_{4}-4)\\\Rightarrow 2=-(a_{4}-4)\\\Rightarrow -2=(a_{4}-4)\\\Rightarrow -2+4=a_{4}\\\Rightarrow a_{4}=2[/tex]
Putting n = 5 in the recursive function:
[tex]a_5=a_{4}-(a_{3}-4)\\\Rightarrow -2=2-(a_{3}-4)\\\Rightarrow -2-2=-(a_{3}-4)\\\Rightarrow 4=(a_{3}-4)\\\Rightarrow a_{3}=8[/tex]
Putting n = 4 in the recursive function:
[tex]a_4=a_{3}-(a_{2}-4)\\\Rightarrow 2=8-(a_{2}-4)\\\Rightarrow 2-8=-(a_{2}-4)\\\Rightarrow 6=(a_{2}-4)\\\Rightarrow a_{2}=10[/tex]
Putting n = 3 in the recursive function:
[tex]a_3=a_{2}-(a_{1}-4)\\\Rightarrow 8=10-(a_{1}-4)\\\Rightarrow 8-10=-(a_{1}-4)\\\Rightarrow -2=-(a_{1}-4)\\\Rightarrow 2=a_{1}-4\\\Rightarrow a_{1}=4+2\\\Rightarrow a_{1}=6[/tex]
So, first, second and third terms are 6, 10, 8.
