Math, asked by daveakshita2005, 8 months ago

Prove that √3 is an irrational number​

Answers

Answered by Hɾιтհιĸ
28

assume root 3 as rational number

then, as we know a rational number should be in the form of p/q

where p and q are co- prime number.

So,

√3 = p/q { where p and q are co- prime}

√3q = p

Now, by squaring both the side

we get,

(√3q)² = p²

3q² = p² ........ ( i )

So,

if 3 is the factor of p²

then, 3 is also a factor of p ..... ( ii )

=> Let p = 3m { where m is any integer }

squaring both sides

p² = (3m)²

p² = 9m²

putting the value of p² in equation ( i )

3q² = p²

3q² = 9m²

q² = 3m²

So,

if 3 is factor of q²

then, 3 is also factor of q

Since

3 is factor of p & q both

So, our assumption that p & q are co- prime is wrong

hence,. √3 is an irrational number

Answered by Mihir1001
2
\huge{\underline{\mathfrak{\textcolor{blue}{Answer :}}}} \LARGE\boxed{\fcolorbox{pink}{pink}{irrational}}
\huge{\underline{\mathrm{\textcolor{red}{Step-by-step \: \: explanation :}}}}

\LARGE{\underline{\mathtt{\textcolor{violet}{Given :-}}}}
⚪ root over 3 [ √3 ]

\LARGE{\underline{\mathtt{\textcolor{green}{To \: \: prove :-}}}}
 \sqrt{3} is an irrational number.

\LARGE{\underline{\mathtt{\textcolor{teal}{Concept \: \: used :-}}}}
⚪ Real numbers
⚪ Irrational numbers

\LARGE{\underline{\mathtt{\textcolor{blue}{Proof :-}}}}
✒ If possible,  \sqrt{3} be a rational number.

let  \sqrt{3} = \Large{ \frac{a}{b} }, where a and b are co-primes and b ≠ 0.

Then,
 \sqrt{3} = \Large{ \frac{a}{b} }

On squaring both the sides :

 \Rightarrow { \left( \sqrt{3} \right) }^{2} = \Large{ { \left( \frac{a}{b} \right) }^{2} }

 \Rightarrow 3 = \Large{ \frac{ {a}^{2} }{ {b}^{2} } }

 \Rightarrow 3 {b}^{2} = {a}^{2}

 \Rightarrow {a}^{2} = 3 {b}^{2} ——————— ( 1 )

Therefore,  {a}^{2} is divisible by 3.
Therefore, a is also divisible by 3.

let a = 3c, for some integer c. ——————— ( 2 )

On substituting ( 2 ) in ( 1 ) , we get :

 {(3c)}^{2} = 3 {b}^{2}

 \Rightarrow 9 {c}^{2} = 3 {b}^{2}

 \Rightarrow  {}^{3}  \:  \cancel{9}  {c}^{2} =  {}^{1}  \:  \cancel{5} {b}^{2}

 \Rightarrow {b}^{2} = 3 {c}^{2}

Therefore,  {b}^{2} is divisible by 3.
Therefore, b is also divisible by 3.

Therefore, a and b have a common factor 3.
This contradicts the fact that a and b are co-primes.
This contradiction arises on assuming  \sqrt{5} to be a rational number.
So, our assumption is wrong.
Hence,  \sqrt{3} is an \sf\green{\underline{\blue{irrational \: number}}}.

\LARGE{\underline{\mathtt{\textcolor{magenta}{Conclusion :-}}}}
 \sqrt{3} is an \sf\green{\underline{\blue{irrational \: number}}}.

{\textcolor{purple}{\fcolorbox{teal}{cyan}{Your \: required \: answer \: is \: above......... keep \: smiling........ ;-D}}}
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\bold{hope………. \: this \: answer \: helps \: you \: the \: best .}
and…… mark this answer as ❤BRAINLIEST❤

Thanks for reading…………………………………………………….. =)
\LARGE{\fcolorbox{orange}{orange}{brainliest answer}}

\mid \underline{\LARGE\bf\green{Brainliest \: Answer}}\mid
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