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Bunuel
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Hello Bunuel,

I too have the same question as Xavipersonal. How does the expression in bracker of \(x^{(x^{x^{...}})}\) end up as 2? Is this some kind of a rule?

Thanks in advance for your answer!
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susheelh
Hello Bunuel,

I too have the same question as Xavipersonal. How does the expression in bracker of \(x^{(x^{x^{...}})}\) end up as 2? Is this some kind of a rule?

Thanks in advance for your answer!

Let me ask you: does the expression in brackets differ from the expression which equals to 2 in any way?

Similar questions:
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https://gmatclub.com/forum/new-tough-an ... l#p1029228
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I think this is a high-quality question and I agree with explanation.
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I have edited the question and the solution by adding more details to enhance its clarity. I hope it is now easier to understand.
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I think this is a high-quality question and I agree with explanation.
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If x^(some number) = 2, then x has to be sqroot(2) since the only way to achieve the value "2" through exponents is Sqroot(2) raised to the power 2. So, x = sqroot2 and the exponent they have defined equates to 2.
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Given that the expression extends to an infinite number of exponents, the expression inside the parentheses would also equal 2. Why it is equal to 2. ? Can you explain please

Bunuel
Official Solution:

If \(x>0\) and the expression \(x^{x^{x^{...}}}\), where the given expression extends to an infinite number of exponents, equals 2, then what is the value of \(x\)?

A. \(\frac{1}{2}\)


B. \(\sqrt[4]{2}\)


C. \(\sqrt{2}\)


D. \(\sqrt{3}\)


E. \(2\)


Re-write as: \(x^{(x^{x^{...}})}\). Given that the expression extends to an infinite number of exponents, the expression inside the parentheses would also equal 2. This allows us to substitute the value inside the parentheses with 2 and rewrite the given expression as \(x^2=2\). Hence, \(x = \sqrt{2}\).


Answer: C
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pyreddy
Given that the expression extends to an infinite number of exponents, the expression inside the parentheses would also equal 2. Why it is equal to 2. ? Can you explain please

Bunuel
Official Solution:

If \(x>0\) and the expression \(x^{x^{x^{...}}}\), where the given expression extends to an infinite number of exponents, equals 2, then what is the value of \(x\)?

A. \(\frac{1}{2}\)


B. \(\sqrt[4]{2}\)


C. \(\sqrt{2}\)


D. \(\sqrt{3}\)


E. \(2\)


Re-write as: \(x^{(x^{x^{...}})}\). Given that the expression extends to an infinite number of exponents, the expression inside the parentheses would also equal 2. This allows us to substitute the value inside the parentheses with 2 and rewrite the given expression as \(x^2=2\). Hence, \(x = \sqrt{2}\).


Answer: C
We can safely assume that the expression equals x because it's an example of a recursive or self-referential structure. Since the same expression repeats infinitely, we can replace the part inside the brackets with x. This is a common technique when solving problems involving continued roots or similar recursive patterns.

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Hope it helps.­
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I like the solution - it’s helpful.
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I like the solution - it’s helpful.
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I did not quite understand the solution. I dont understand this question quite. Please help me in this.
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I did not quite understand the solution. I dont understand this question quite. Please help me in this.
Please review the discussion above carefully and check the linked similar questions for additional practice. If anything remains unclear, feel free to ask specific questions, and I’ll be happy to explain further.
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