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Show that there exist irrational numbers x,yx,y for which xyx^y is rational

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Q. Show that there exist irrational numbers x,yx,y for which xyx^y is rational
  1. Consider 2\sqrt{2}: Let's consider the number 2\sqrt{2}, which is known to be irrational. We want to find another irrational number yy such that (2)y(\sqrt{2})^y is rational.
  2. Choose irrational number: Let's take yy to be the irrational number log2(2)\log_{2}(\sqrt{2}). The logarithm of a number to its own base is 12\frac{1}{2}, which is rational, but the expression log2(2)\log_{2}(\sqrt{2}) itself is irrational.
  3. Calculate (2)y(\sqrt{2})^y: Now, let's calculate (2)y(\sqrt{2})^y using the value of yy we have chosen. We have y=log2(2)y = \log_2(\sqrt{2}), so (2)y=(2)log2(2)(\sqrt{2})^y = (\sqrt{2})^{\log_2(\sqrt{2})}.
  4. Apply property of exponents: Using the property of exponents and logarithms, we know that alogb(a)=ba^{\log_b(a)} = b. Applying this property to our expression, we get (2)log2(2)=212(\sqrt{2})^{\log_{2}(\sqrt{2})} = \sqrt{2}^{\frac{1}{2}}.
  5. Simplify expression: Simplifying 212\sqrt{2}^{\frac{1}{2}}, we get (2)12=(2)24=(22)14=214(\sqrt{2})^{\frac{1}{2}} = (\sqrt{2})^{\frac{2}{4}} = (\sqrt{2^2})^{\frac{1}{4}} = 2^{\frac{1}{4}}.
  6. Reach contradiction: Since 2142^{\frac{1}{4}} is simply the fourth root of 22, which is 2\sqrt{2}, we have shown that our initial irrational number 2\sqrt{2} raised to the power of another irrational number log2(2)\log_{2}(\sqrt{2}) results in 2\sqrt{2}, which is irrational. This is a contradiction to our goal, so we need to reconsider our approach.

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