Principle Of Mathematical Induction CBSE Questions & Answers

Principle Of Mathematical Induction

This is Mathematics Class 11 Principle of Mathematical Induction CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
Let \(P\left( n \right)\) be a statement and let \(P\left( n \right) \Rightarrow P\left( {n + 1} \right)\) for all natural numbers n , then \(P\left( n \right)\) is true for
  • A
    all n
  • B
    all n \(>\) 1
  • C
    nothing can be said
    Correct
  • D
    all n > m , m being a fixed positive integer
2
Let \(P\left( n \right)\) b e a statement \({2^n} < n!\) , where n is a natural number , then \(P\left( n \right)\) is true for
  • A
    all n \(>\) 3
    Correct
  • B
    all n \(>\) 2
  • C
    none of these
  • D
    all n
3
If x \(>\) -1 , then the statement \({\left( {1 + x} \right)^n} > 1 + nx\) is true for
  • A
    all n \(>\) 1 provided x \( \ne \) 0
    Correct
  • B
    all n \(>\) 1
  • C
    none of these
  • D
    all n \( \in \) N
4
The smallest +ve integer n , for which\( n! < \)\({\left( {{{n + 1} \over 2}} \right)^n}\) holds is
  • A
    4
  • B
    1
  • C
    3
  • D
    2
    Correct
5
If P ( n ) = 2+4+6+………………..+2n , n \( \in \) N , then P ( k ) = k ( k + 1 ) + 2 \( \Rightarrow \) P ( k + 1 ) = ( k + 1 ) ( k +2 ) + 2 for all k \( \in \) N . So we can conclude that P ( n ) = n ( n + 1 ) +2 for
  • A
    n \(>\) 1
  • B
    all n \( \in \) N
  • C
    n \(>\) 2
  • D
    nothing can be said
    Correct
6
\(x\left( {{x^{n - 1}} - n{a^{n - 1}}} \right) + {a^n}\left( {n - 1} \right)\) is divisible by \({\left( {x - a} \right)^2}\) for
  • A
    none of these.
  • B
    all n \( \in \) N
    Correct
  • C
    n \(>\) 1
  • D
    n \(>\) 2
7
The greatest positive integer , which divides n ( n + 1 ) ( n + 2 ) ( n + 3 ) for all n \( \in \) N , is
  • A
    2
  • B
    120
  • C
    6
  • D
    24
    Correct
8
Let P ( n ) denote the statement \({n^2} + n\) is odd , It is seen that \(P\left( n \right) \Rightarrow P\left( {n + 1} \right)\) , therefore P ( n ) is true for all
  • A
    none of these
    Correct
  • B
    n \(>\) 2
  • C
    n \(>\) 1
  • D
    n
9
The greatest positive integer, which divides \(\left( {n + 1} \right)\left( {n + 2} \right)\left( {n + 3} \right)..................\left( {n + r} \right)\forall n \in W\) , is
  • A
    n+r
  • B
    \({\text{r }}!\)
    Correct
  • C
    \(\left( {{\text{ r }} + {\text{ 1 }}} \right){\text{ }}!\)
  • D
    r
10
The statement P ( n ) : “\({\text{1 X 1}}!{\text{ }} + {\text{ 2 X 2}}!{\text{ }} + {\text{ 3 X 3}}!{\text{ }} + {\text{ }} \ldots .. + {\text{ n X n}}!{\text{ }} = {\text{ }}\left( {{\text{ n }} + {\text{ 1 }}} \right){\text{ }}!--{\text{ 1}}\) “ is
  • A
    for all n \( \in \) N
    Correct
  • B
    not true for any n
  • C
    true for all n \(>\) 1
  • D
    none of these
11
A student was asked to prove a statement P ( n ) by method of induction . He proved that P ( 3 ) is true and that \(P\left( n \right) \Rightarrow P\left( {n + 1} \right)\) for all natural numbers n . On the basis of this he could conclude that P ( n ) is true
  • A
    for all n \( \in \) N
  • B
    for no n
  • C
    none of these
  • D
    for all n\(≥\)3
    Correct
12
\({3^{2n + 2}} - 8n - 9\) is divisible by 64 for all
  • A
    n \( \in \) N , n \(≥\)2
  • B
    n \( \in \) N , n \(>\) 2
  • C
    none of these.
  • D
    n \( \in \) N
    Correct
13
The inequality \(n! > {2^{n - 1}}\) is true
  • A
    for all n \(>\) 1
  • B
    for no n \( \in \) N
  • C
    for all n\( \)> 2
    Correct
  • D
    for all n \( \in \) N
14
The statement \({3^n} > 4n\) is true for all
  • A
    n \(>\) 1 , n \( \in \) N
    Correct
  • B
    n \(>\) 2 , n \( \in \) N
  • C
    n \( \in \) N
  • D
    none of these
15
The statement \({2^n} > 3n\) is true for all
  • A
    n \(>\) 4
  • B
    n \( \in \) N
  • C
    none of these.
  • D
    n \(>\) 3
    Correct