Q. Show that there exist irrational numbers x,y for which xy is rational
Consider 2: Let's consider the number 2, which is known to be irrational. We want to find another irrational number y such that (2)y is rational.
Choose irrational number: Let's take y to be the irrational number log2(2). The logarithm of a number to its own base is 21, which is rational, but the expression log2(2) itself is irrational.
Calculate (2)y: Now, let's calculate (2)y using the value of y we have chosen. We have y=log2(2), so (2)y=(2)log2(2).
Apply property of exponents: Using the property of exponents and logarithms, we know that alogb(a)=b. Applying this property to our expression, we get (2)log2(2)=221.
Simplify expression: Simplifying 221, we get (2)21=(2)42=(22)41=241.
Reach contradiction: Since 241 is simply the fourth root of 2, which is 2, we have shown that our initial irrational number 2 raised to the power of another irrational number log2(2) results in 2, which is irrational. This is a contradiction to our goal, so we need to reconsider our approach.
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