Which of the following is equivalent to 21^(1/2)/6 ?

Question

Which of the following is equivalent to  \frac{\sqrt{21}}{6} ?

A.  \frac{\sqrt{7}}{2}

B.  \sqrt{\frac{7}{2}}

C.  \sqrt{\frac{7}{12}}  
 
D.  \frac{7}{\sqrt{6}}

E.  \frac{21\sqrt{6}}{6}

JeffTargetTestPrep · Accepted Answer

Let’s simplify the given expression:

√(21)/6 = √(21)/√(36) = √(21/36) = √(7/12)

Answer: C

rohit8865 · Answer

multiply and divide by √21 to get 21/(6*√21)
or 7/2√21

or √49/√(4*21)

or √(49/84)

√7/12--------(dividing by 7)

Ans C

quantumliner · Answer

√21/6, can be written as √21/(√4 * √9)

=> Cancelling out √3 from numerator and denominator, we get √7/(√4 * √3)

=> Above can be written as √7/√12

Therefore, Answer is C

ehsan090 · Answer

why you took denominator in root any particular reason
TIA

rohit8865 · Answer

because you have to reduce the expresson and we can reduce by cancelling factor 3 which is present in both num. & denominator

Abhishek009 · Answer

Square both Numerator and Denominator :  \frac{21}{36}  =>  \frac{7}{12}

Since, we have taken square both in numerator and denominator, the actual value of the fraction will be :  \sqrt{\frac{7}{12}}

Hence, answer must be (C)  \sqrt{\frac{7}{12}}

ehsan090 · Answer

why you took denominator in root any particular reason TIA because you have to reduce the expresson and we can reduce by cancelling factor 3 which is present in both num. & denominator

Thanks mate a little clear. I need to practice these type of question for more clear understanding

mamun2871 · Answer

√21/6
=√3*√7/3*2
=√7/√3*√4 as √4=2
=√7/√12
=√(7/12) Hence, Answer is C

khumoyuns · Answer

sqrt (21) / 6 is less than 1

The only option in the answer choices that is less than 1 is C.

Hope this helps

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Which of the following is equivalent to 21^(1/2)/6 ?

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Which of the following is equivalent to 21^(1/2)/6 ?

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