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If the equation x^2-3kx+2e^(2logk)-1=0 h...

If the equation `x^2-3kx+2e^(2logk)-1=0` has real roots such that the product of roots is `7` then the value of `k` is

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To solve the equation \( x^2 - 3kx + 2e^{2\log k} - 1 = 0 \) given that the product of the roots is 7, we can follow these steps: ### Step 1: Rewrite the equation The equation can be rewritten as: \[ x^2 - 3kx + (2e^{2\log k} - 1) = 0 \] ### Step 2: Simplify \( e^{2\log k} \) Using the property of logarithms, we know that: \[ e^{\log a} = a \] Thus, we can simplify \( e^{2\log k} \): \[ e^{2\log k} = (e^{\log k})^2 = k^2 \] So, the equation becomes: \[ x^2 - 3kx + (2k^2 - 1) = 0 \] ### Step 3: Use the product of roots For a quadratic equation of the form \( ax^2 + bx + c = 0 \), the product of the roots is given by: \[ \text{Product of roots} = \frac{c}{a} \] In our case, \( a = 1 \), \( b = -3k \), and \( c = 2k^2 - 1 \). Therefore, the product of the roots is: \[ \frac{2k^2 - 1}{1} = 2k^2 - 1 \] We know from the problem statement that this product equals 7: \[ 2k^2 - 1 = 7 \] ### Step 4: Solve for \( k \) Now, we can solve for \( k \): \[ 2k^2 - 1 = 7 \] Adding 1 to both sides: \[ 2k^2 = 8 \] Dividing both sides by 2: \[ k^2 = 4 \] Taking the square root of both sides: \[ k = 2 \quad \text{or} \quad k = -2 \] ### Step 5: Determine valid values of \( k \) Since \( k \) is the input of a logarithm, it must be positive. Therefore, we reject \( k = -2 \) and accept: \[ k = 2 \] ### Final Answer The value of \( k \) is: \[ \boxed{2} \]

To solve the equation \( x^2 - 3kx + 2e^{2\log k} - 1 = 0 \) given that the product of the roots is 7, we can follow these steps: ### Step 1: Rewrite the equation The equation can be rewritten as: \[ x^2 - 3kx + (2e^{2\log k} - 1) = 0 \] ...
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