How do you find the first five terms of each sequence $a_1=12$ , $a_(n+1)=a_n-3$ ?

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Answer 1 · 2016-10-18T17:55:32

The first 5 terms are $12, 9, 6, 3, 0$

$a_(n+1)=a_n-3$ and $a_1=12$

Find the first five terms.

This is a recursively defined sequence, which means you use the previous term to find the next.

The first term is $a_1=12$ .

The 2nd term is $a_2=a_(1+1)=a_1-3=12-3=9$

The 3rd term is $a_3=a_(2+1)=a_2-3=9-3=6$

Note that you are subtracting 3 to find the next term.

So, $a_4=3$ and $a_5=0$ .

The first 5 terms are $12, 9, 6, 3, 0$ .

How do you find the first five terms of each sequence a_1=12a_1=12, a_(n+1)=a_n-3a_(n+1)=a_n-3?