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If a!= 1 and In a^2 + (In a^2)^2 + (In a...

If `a!= 1` and `In a^2 + (In a^2)^2 + (In a^2)^3 + ... = 3 (ln a + (lna)^2 + (lna)^3 + (lna)^4+...)` then 'a' is equal to

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To solve the equation given in the problem, we start by rewriting the infinite series on both sides of the equation. ### Step 1: Write the equation We have: \[ \ln a^2 + (\ln a^2)^2 + (\ln a^2)^3 + \ldots = 3 \left( \ln a + (\ln a)^2 + (\ln a)^3 + (\ln a)^4 + \ldots \right) \] ### Step 2: Use properties of logarithms Using the property of logarithms, we can rewrite \(\ln a^2\) as: \[ \ln a^2 = 2 \ln a \] Thus, the left-hand side becomes: \[ 2 \ln a + (2 \ln a)^2 + (2 \ln a)^3 + \ldots \] ### Step 3: Identify the series as a geometric series The left-hand side is a geometric series with first term \(2 \ln a\) and common ratio \(2 \ln a\). The sum of an infinite geometric series can be calculated using the formula: \[ S = \frac{a}{1 - r} \] where \(a\) is the first term and \(r\) is the common ratio. Therefore, we have: \[ \text{Left-hand side} = \frac{2 \ln a}{1 - 2 \ln a} \] ### Step 4: Analyze the right-hand side The right-hand side is also a geometric series with first term \(\ln a\) and common ratio \(\ln a\): \[ \text{Right-hand side} = 3 \left( \frac{\ln a}{1 - \ln a} \right) \] ### Step 5: Set the two sides equal Now we set the left-hand side equal to the right-hand side: \[ \frac{2 \ln a}{1 - 2 \ln a} = 3 \left( \frac{\ln a}{1 - \ln a} \right) \] ### Step 6: Cross-multiply to eliminate the fractions Cross-multiplying gives: \[ 2 \ln a (1 - \ln a) = 3 \ln a (1 - 2 \ln a) \] ### Step 7: Expand both sides Expanding both sides results in: \[ 2 \ln a - 2 (\ln a)^2 = 3 \ln a - 6 (\ln a)^2 \] ### Step 8: Rearrange the equation Rearranging gives: \[ 4 (\ln a)^2 - \ln a = 0 \] ### Step 9: Factor the equation Factoring out \(\ln a\): \[ \ln a (4 \ln a - 1) = 0 \] ### Step 10: Solve for \(\ln a\) This gives us two solutions: 1. \(\ln a = 0\) (which implies \(a = 1\), but we are given \(a \neq 1\)) 2. \(4 \ln a - 1 = 0\) which leads to: \[ \ln a = \frac{1}{4} \] ### Step 11: Exponentiate to find \(a\) Exponentiating both sides gives: \[ a = e^{\frac{1}{4}} \] ### Final Answer Thus, the value of \(a\) is: \[ a = e^{\frac{1}{4}} \] ---
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