Prove the statement by the Principle of Mathematical Induction: $n^{2} < 2^{n}$ for all natural numbers $n \geq 5$.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) Let $P(n): n^{2} < 2^{n}$ for $n \geq 5, n \in \mathbb{N}$.
Step $1$: For $n = 5$,$P(5): 5^{2} < 2^{5} \implies 25 < 32$,which is true.
Step $2$: Assume $P(k)$ is true for some $k \geq 5$,i.e.,$k^{2} < 2^{k}$.
We need to show $P(k+1): (k+1)^{2} < 2^{k+1}$ is true.
Consider $(k+1)^{2} = k^{2} + 2k + 1$.
Since $k^{2} < 2^{k}$,we have $(k+1)^{2} < 2^{k} + 2k + 1$.
For $k \geq 5$,it can be shown that $2k + 1 < k^{2} < 2^{k}$.
Thus,$(k+1)^{2} < 2^{k} + 2^{k} = 2 \cdot 2^{k} = 2^{k+1}$.
Therefore,$P(k+1)$ is true whenever $P(k)$ is true.
By the Principle of Mathematical Induction,$P(n)$ is true for all $n \geq 5$.

Explore More

Similar Questions

Prove the following by using the principle of mathematical induction for all $n \in N$:
$\frac{1}{1 \cdot 4} + \frac{1}{4 \cdot 7} + \frac{1}{7 \cdot 10} + \ldots + \frac{1}{(3n-2)(3n+1)} = \frac{n}{3n+1}$

For all $n \in \mathbb{N}$,if $1^2+2^2+3^2+\ldots+n^2 > x$,then $x=$

Prove the following by using the principle of mathematical induction for all $n \in N$:
$\frac{1}{3 \times 5} + \frac{1}{5 \times 7} + \frac{1}{7 \times 9} + \ldots + \frac{1}{(2n+1)(2n+3)} = \frac{n}{3(2n+3)}$

Use the Principle of Mathematical Induction to show that for a sequence $a_{1}, a_{2}, a_{3}, \ldots$ defined by $a_{1}=3$ and $a_{k}=7 a_{k-1}$ for all natural numbers $k > 1$,the general term is $a_{n}=3 \cdot 7^{n-1}$ for all $n \in N$.

Difficult
View Solution

Use the Principle of Mathematical Induction to show that for a sequence $b_{0}, b_{1}, b_{2}, \ldots$ defined by $b_{0}=5$ and $b_{k}=4+b_{k-1}$ for all natural numbers $k$,the general term is $b_{n}=5+4n$ for all natural numbers $n$.

Difficult
View Solution

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo