NCERT Class 11-Math's: Chapter –9 Sequence and Series Part 5

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Objective Type Questions

Choose the correct answer out of the four given options in Examples 14 to 23 (M.C.Q.).

Question 14:

A sequence may be defined as a

(A) Relation, whose range (natural numbers)

(B) Function whose range

(C) Function whose domain

(D) Progression having real values

Solution (C) is the correct answer.

A sequence is a function having domain

Question 15:

If are positive integers then value of expression is

(A)

(B)

(C)

(D)

Answer:

(B) Is the correct answer, since

A.M. > GM.,

Multiplying the three inequalities, we get

Or,

Question 16:

In a G.P. of positive terms, if any term is equal to the sum of the next two terms. Then the common ratio of the G.P. is

(A)

(B)

(C)

(D)

Answer:

(D) Is the correct answer, since

Therefore,

Question 17:

In an A.P. the term is q and the term is . Then the term is

(A)

(B

(C)

(D)

Answer:

(B) Is the correct answer

Let be the first term and common difference respectively.

Therefore,

Subtracting (1), from (2) we get

Substituting in (1) we get

Now

Question 18:

Let be the sum, be the product and R be the sum of the reciprocals of terms of a G.P. Then is equal to

(A)

(B) (Common ratio)

(C) (First term) (common ratio)

(D) None of these

Answer:

(A) Is the correct answer

Let us take a G.P. with three terms . Then

Therefore, the ratio is