RD Sharma Class 10 Solutions Chapter 9 Arithmetic Progressions Ex 9.2

RD Sharma Class 10 Solutions Arithmetic Progressions Exercise 9.2

Question 1.
Show that the sequence defined by a_n = 5n – 7 is an A.P., find its common difference.
Solution:

Question 2.
Show that the sequence defined by a_n = 3n² – 5 is not an A.P.
Solution:

Question 3.
The general term of a sequence is given by a_n = -4n + 15. Is the sequence an A.P.? If so, find its 15th term and the common difference.
Solution:
General term of a sequence
a_n = -4n + 15

Question 4.
Write the sequence with nth term :
(i) a_n = 3 + 4n
(ii) a_n = 5 + 2n
(iii) a_n = 6 – n
(iv) a_n = 9 – 5n
Show that all of the above sequences form A.P.
Solution:

Question 5.
The nth term of an A.P. is 6n + 2. Find the common difference. [CBSE 2008]
Solution:

Question 6.
Justify whether it is true to say that the sequence, having following nth term is an A.P.
(i) a_n = 2n – 1
(ii) a_n = 3n² + 5
(iii) a_n = 1 + n + n²
Solution: