# maths

posted by .

The 2nd term in a geometric sequence is -4 and the 5th term is 32

• maths -

a + ar + a r^2 + a r^3 + a r^4

ar = -4
a r^4 = 32

a = -4/r

(-4/r) r^4 = 32

r^3 = -8
so r = -2
and a = 2

## Similar Questions

1. ### Maths

The 5th term of an exponential sequence is 4 and of 2nd term is 35(¡)find the 3rd term (¡¡)the 6th term (¡¡¡)the sum of the first 5th term?
2. ### maths

The 2nd term in Geometric sequence is -4 and the 5th is 32 ,find the general formula \term and the first 3 terms ,find the 18th term
3. ### math Question

the 5th term in a geometric sequence is 160. The 7th term is 40. What are the possible values of the 6th term of the sequence +70 70 +80 80
4. ### geometric sequence

The sum of the 2nd and 5th terms of a geometric sequence is 3.5. The sum of the 3rd and 6th is -7. Determine the ratio r of the sequence and the first term a.
5. ### geometric progression

the 3rd term of a gpis 10 and the 6th term is 80 find the common ratio No2 if the 2nd term of a gp is 4 and the 5th term is 1over 16,the7th term is_
6. ### math

The 3rd term of a geometric progression is nine times the 1st term.if the 2nd term is one twenty fourth the 5th term.find the 4th term.(there is a mistake in the 2nd to the last statement.help locate the mistake{final answer 4th term …
7. ### Math

The 6th term of an arithmetic sequence is 3 times the 2nd term. Prove that the 10th term is twice the 5th term. tn=t1+(n-1)d
8. ### Algebra

I am so lost on these problems. Write a geometric sequence that starts with 3 and has a common ratio of 5. What is the 23rd term in the sequence. Write an arithmetic sequence that has a common difference of 4 and the eighth term is …
9. ### Maths

The 5th term of an arithmetic progression is 3times of 2nd term and 12th term exceeds 2times of 6th term by 1. Find the 16th term
10. ### algebra1

Which of the following functions represents a geometric sequence?

More Similar Questions