2 Answers

Voddan · Answer 1 · 2020-07-29T01:54:43+0000

Answer:

The first five terms for given recursive formula are -1, 2, 8, 20, 44.

Explanation:

Given:

a_1 = -1

The recursive formula given is;

a_n=2(a_(n-1))+4

Now we will find the first five terms using above formula.

We know the first term hence we find rest of the term.

when n=2;

$a_2 = 2(a_(2-1))+4\\a_2=2(a_1)+4\\a_2=2*-1+4\\a_2= -2+4\\a_2=2$

when n=3;

$a_3 = 2(a_(3-1))+4\\a_3=2(a_2)+4\\a_3=2* 2+4\\a_3= 4+4\\a_3=8$

when n=4;

$a_4 = 2(a_(4-1))+4\\a_4=2(a_3)+4\\a_4=2* 8+4\\a_4= 16+4\\a_4=20$

when n=5;

$a_5 = 2(a_(5-1))+4\\a_5=2(a_4)+4\\a_5=2* 20+4\\a_5= 40+4\\a_5=44$

Hence the first five terms for given recursive formula is -1, 2, 8, 20, 44.

Please log in or register to add a comment.