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If x^(1/6) = 6, then (x^6)^(1/2) =

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If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 15 Jan 2018, 06:07
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D
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Question Stats:

74% (01:13) correct 26% (01:20) wrong based on 174 sessions

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If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 15 Jan 2018, 07:46
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)


(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)


\(\sqrt[6]{x}=6\), raise both sides to the power \(6\)

\(=>x=6^6\). again raise both sides to the power \(6\)

\(=>x^6=(6^6)^6=6^{36}=(6^{18})^2\). Now take square root of both the sides

=>\(\sqrt{x^6}=\sqrt{(6^{18})^2}=6^{18}\)

Option D
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Re: If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 15 Jan 2018, 07:52
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)


(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)



\(\sqrt[6]{x}=6........x=6^6\)
\(\sqrt{x^6} = x^{\frac{6}{2}}=x^3=(6^6)^3=6^{18}\)
D
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Re: If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 15 Jan 2018, 09:40
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)


(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)


\(\sqrt[6]{x}=6\)

So, \(x = 6^6\)

And, \(x^6 = 6^{36}\)

Thus, \(\sqrt{x^6} = 6^{18}\), answer will be (D)
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Re: If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 31 May 2018, 03:04
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)


(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)



\(x^{(1/6)} = 6\)

\(x = 6^6\)

\(\sqrt{6^{36}}\)

\(6^{(18)}\)
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Re: If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 01 Jun 2018, 11:22
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)


(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)


Raising both sides of the first equation to the 6th power, we have:

x = 6^6

So [(6^6)^6]^1/2 = (6^36)^1/2 = 6^18.

Answer: D
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If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 03 Jun 2018, 04:21
niks18 wrote:
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)


(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)


\(\sqrt[6]{x}=6\), raise both sides to the power \(6\)

\(=>x=6^6\). again raise both sides to the power \(6\)

\(=>x^6=(6^6)^6=6^{36}=(6^{18})^2\). Now take square root of both the sides

=>\(\sqrt{x^6}=\sqrt{(6^{18})^2}=6^{18}\)

Option D



hi there generis, today is International Exponents Day :) so happy day :) may you always have "positive exponents" :)

can you please explain one thing :)

for example when we raise both parts to the power of 6

\(=>x=6^6\) we multiply both sides by power 6

so we get \(x^6=6^{36}\)

now when i need to take a square root, does it mean that i need to multiply both sides by the exponent of \({1/2}\) , because radical sign means raised to the power of \(\frac{1}{2}\)
for example \(\sqrt{16}\) is the same as \(16^{\frac{1}{2}}\)

so taking square root from both parts \(x^6=6^{36}\) means \(x^6^{\frac{1}{2}}=6^{36}^{\frac{1}{2}}\) which is \(x^3=6^{18}\) :? ??

many thanks and happy sunday :-)
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If x^(1/6) = 6, then (x^6)^(1/2) =  [#permalink]

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New post 03 Jun 2018, 10:23
1
dave13 wrote:
niks18 wrote:
Bunuel wrote:
If \(\sqrt[6]{x}=6\), then \(\sqrt{x^6} =\)

(A) \(6\)

(B) \(6\sqrt{6}\)

(C) \(6^6\)

(D) \(6^{18}\)

(E) \(6^{36}\)

\(\sqrt[6]{x}=6\), raise both sides to the power \(6\)

\(=>x=6^6\). again raise both sides to the power \(6\)

\(=>x^6=(6^6)^6=6^{36}=(6^{18})^2\). Now take square root of both the sides

=>\(\sqrt{x^6}=\sqrt{(6^{18})^2}=6^{18}\)

Option D

hi there generis, today is International Exponents Day :) so happy day :) may you always have "positive exponents" :)

can you please explain one thing :)

for example when we raise both parts to the power of 6

\(=>x=6^6\) we multiply both sides by power 6

so we get \(x^6=6^{36}\)

now when i need to take a square root, does it mean that i need to multiply both sides by the exponent of \((\frac{1}{2})\) , because radical sign means raised to the power of \(\frac{1}{2}\)
for example \(\sqrt{16}\) is the same as \(16^{\frac{1}{2}}\)

so taking square root from both parts \(x^6=6^{36}\) means \(x^6^{\frac{1}{2}}=(6^{36})^{\frac{1}{2}}\) which is \(x^3=6^{18}\) :? ??

many thanks and happy sunday :-)

Quote:
now when i need to take a square root, does it mean that i need to multiply both sides by the exponent of \({1/2}\) , because radical sign means raised to the power of \(\frac{1}{2}\)

Hi dave13 , yes, you are correct. :-) "Take the square root" = raise the base to the power of \(\frac{1}{2}\). Often, the exponents get multiplied, just as you have done.

I think you wonder why your answer looks different. Its substance is NOT different.

These different forms of the expression all mean the same thing:
\(\sqrt{x^6}\)

\((x^6)^{\frac{1}{2}}\)

\(x^{(6*\frac{1}{2})}\)

\(x^3\)

Last one is the same because: \(x^{(6*\frac{1}{2})}=(x)^{((6*\frac{1}{2})=3)}=x^3\)

The prompt asked about this form of the term: \(\sqrt{x^6}\). So posters above stayed with that form. That's the only difference. Form.

Form can be tricky. You simplified both sides. The answer requires us to simplify only RHS.

Not having to simplify \(\sqrt{x^6}\) to \(x^3\) removed one extra step -- the one you took. But your math is correct.

Just watch the form in the question. We can simplify one side without simplifying the other. Simplifying does not change the value of the term.

(Multiplying one side by 2, e.g., does change the value. In that case we would have to multiply the other side by 2.)

I think I got to the heart of your question. If not, ask it a little more specifically. Hope that helps. :-)

P.S. I like your exponent pun, hokey aspect and all. Made me grin. Your avatar makes perfect sense.
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