Q1. Write a recursive formula for the geometric sequence whose third term is
fourth term is
.
and
Q2. Write a recursive formula for the geometric sequence whose third term is
fourth term is
.
and
Q3. Write a recursive formula for the sequence:
5,11,17,23,29……….
Q4. Write a recursive formula for the sequence:
9,13,17,21,25……………
Q5. Given the recursive formula for a sequence, find the explicit formula for the sequence.
an= an-1
a1=
Q6. Given the recursive formula for a sequence, find the explicit formula for the sequence.
an= an-1
a1=
Q7. Given the recursive formula for a sequence, find the explicit formula for the sequence.
an= an-1
a1=
Q8. Given the explicit formula of a geometric sequence find the first three terms of the
sequence.
Q9. Given the explicit formula of a geometric sequence find the first three terms of the
sequence.
Q10. Write a recursive formula for the geometric sequence whose fourth term is
fifth term is
.
and
Q11. There are 500 fish currently in the pond. 50 fish are added at the end of each year.
The population of fish decreases each year by 10%.Write recursive formula for this
illustration.
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Q12. Using the given explicit formula for the arithmetic sequence, find the 8th and 9th term
of the sequence.
an=
Q13. Using the given explicit formula for the arithmetic sequence, find the 5th and 8th term
of the sequence.
an=
Q14. Using the given explicit formula for the arithmetic sequence, find the 9th and 12th
term of the sequence.
an=
Q15. Write explicit formula for the sequence:
11,14,17,20,23………
Q16. Write explicit formula for the sequence:
7,15,23,31,39…….
Q17. You deposit $30000 in the bank Account paying 4% annual compound interest every
year and you withdraw $5000 at the end of every year. Write a recursive formula that
models the situation.
Q18. You deposit $50000 in the bank Account paying 3% annual compound interest every
year and you again deposit $4000 at the end of every year. Write a recursive formula that
models the situation.
Q19. Given the explicit formula of a geometric sequence find the first four terms of the
sequence.
Q20. Write a recursive formula for the geometric sequence whose sixth term is
term is
.
and fifth
Answers:
A1. an= .an-1 ;
A2. an= .an-1 ;
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A3. an= an-1+6 , a1=5
A4. an= an-1+4 , a1=9
A5. an=
A6. an=
A7. an=
A8.
A9. 4,2,1
A10. an= .an-1 ;
Q.11. P0=500
Pn = Pn-1 (0.9)+50
A12. 8th term=-59, 9th term=-69
A13. 5th term=-40, 8th term=-85
A14. 12th term=-46, 9th term=-31
A15. an=
A16. an=
A17. A0=30000
An = An-1 (1.04)
, n
A18. A0=50000
An = An-1 (1.03)
, n
A19. 9,18,36,72
A20. an= .an-1 ;
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