Discussion of Question with ID = 039 under Square-and-Cube-Roots

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Question

What is the value of ${√17}/6$ − $5/{√17}$?

A

${-13√17}/102$.

B

${+13√17}/102$.

C

${-5√17}/102$.

D

${+5√17}/102$.

Soln.
Ans: a

The given expression can be simplified to ${{(√17)^2} - 6 × 5}/{6 × √17}$, which is same as ${17 - 30}/{6 × √17}$, which is same as ${-13/{6 × √17}$. Rationalizing, we get ${-13/{6 × √17} × {√17/√17}$ which gives ${-13√17}/102$

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