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

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Answer 1 · 2016-10-18T17:55:32

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

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

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 $a_{1} = 12$ $a_1=12$ .

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

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

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

So, $a_{4} = 3$ $a_4=3$ and $a_{5} = 0$ $a_5=0$ .

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

How do you find the first five terms of each sequence a_1=12a1=12a_1=12, a_(n+1)=a_n-3an+1=an−3a_(n+1)=a_n-3?