NCERT Class 11 Mathematics Solutions: Chapter 9 –Sequences and Series Miscellaneous Exercise 9 Part 4
Glide to success with Doorsteptutor material for IEO : fully solved questions with step-by-step explanation- practice your way to success.
Formula for the Nth Term of a Geometric Sequence
1. If f is a function satisfying . for all , such that
, find the value of .
Answer:
It is given that,
for all ……………….eq (1)
Taking in (1),
we obtain
Similarly,
forms a G.P. with both the first term and common ratio equal to
It is known that ,
It is given that,
So, the value of is .
2. The sum of some terms of G.P. is whose first term and the common ratio are , respectively. Find the last term and the number of terms.
Answer:
Consider the sum of n terms of the G.P. be .
It is known that,
It is given that the first term a is and common ratio
Last term of the G.P term
Thus, the last term of the G.P. is .