# Selina Solutions Class 9 Mathematics Solutions for Exercise 1(B) in Chapter 1 - Chapter 1- Rational and Irrational Numbers

Question 14 Exercise 1(B)

Write in descending order:

(i) 𝟐 √𝟔 𝟒 𝒂𝒏𝒅 𝟑 √𝟐 𝟒

(ii) 𝟕√𝟑 𝒂𝒏𝒅 𝟑√𝟕 ^{^4}

\begin{array}{l} 7 \sqrt{3}=\sqrt{7^{2} \times 3}=\sqrt{147} \\ 8 \sqrt{2}=\sqrt{8^{2} \times 2}=\sqrt{128} \end{array}

(i) \begin{array}{l} 2 \sqrt[4]{6}=\sqrt[4]{2}^{4} \times 6=\sqrt[4] 96 \\ 3 \sqrt[4]{2}=\sqrt[4]{3^{4} \times 2}=\sqrt[4]{162} \end{array}

We know that 162 > 96

\begin{array}{l} \Rightarrow \sqrt[4]{162}>\sqrt[4]{96} \\ \Rightarrow 3 \sqrt[4]{2}>2 \sqrt[4]{6} \end{array}

(ii) \begin{array}{l} 7 \sqrt{3}=\sqrt{7^{2} \times 3}=\sqrt{141} \\ 3 \sqrt{7}=\sqrt{3^{2} \times 7}=\sqrt{63} \end{array}

We know that 141 > 63

\begin{array}{l} \Rightarrow \sqrt{141}>\sqrt{63} \\ \Rightarrow 7 \sqrt{3}>3 \sqrt{7} \end{array}

Related Questions

Lido

Courses

Teachers

Book a Demo with us

Syllabus

Maths
CBSE
Maths
ICSE
Science
CBSE

Science
ICSE
English
CBSE
English
ICSE
Coding

Terms & Policies

Selina Question Bank

Maths
Physics
Biology

Allied Question Bank

Chemistry
Connect with us on social media!