Prove that the number sqrt{2} is irrational. | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) Let us assume,to the contrary,that $\sqrt{2}$ is rational. Then,there exist coprime integers $a$ and $b$ $(b 
eq 0)$ such that $\sqrt{2} = \frac{

Vedclass · Accepted Answer

It is an irrational number.

Vedclass · Answer

(B) Let us assume,to the contrary,that $\sqrt{2}$ is rational. Then,there exist coprime integers $a$ and $b$ $(b 
eq 0)$ such that $\sqrt{2} = \frac{a}{b}$. Squaring both sides,we get $2 = \frac{a^2}{b^2}$,which implies $a^2 = 2b^2$. This shows that $a^2$ is even,so $a$ must also be even. Let $a = 2k$ for some integer $k$. Substituting this into the equation,we get $(2k)^2 = 2b^2$,which simplifies to $4k^2 = 2b^2$,or $b^2 = 2k^2$. This shows that $b^2$ is even,so $b$ must also be even. Since both $a$ and $b$ are even,they have a common factor $2$,which contradicts our assumption that $a$ and $b$ are coprime. Therefore,our assumption is false,and $\sqrt{2}$ is irrational.

Prove that the number $\sqrt{2}$ is irrational.

Similar Questions

If the $HCF(a, b) = 25$,then which of the following cannot be the $LCM(a, b)$?

The number $3 \times 15 \times 11 + 11$ is a . . . . . . number.

If the Least Common Multiple $(LCM)$ of $(12, 15, 21) = 500 + 2x$,then $x = $ . . . . . .

The $HCF$ of two numbers is $9$ and their product is $288$. Find their $LCM$.

For two consecutive positive integers $a$ and $b$,what is the value of $\text{HCF}(a, b) \times \text{LCM}(a, b)$?

Vedclass Test Series

Exam Paper Generator

Online Exam Module