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Let x and y be the positive real numbers such that `log_x y=-(1)/(4)`, then value of the expression `log_x(xy^5)-log_y""((x^(2))/(sqrt(y)))` is `(p)/(q)` then q is _____________. { where p , q `in N` and are coprime to each other }

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To solve the problem, we need to evaluate the expression given the condition \( \log_x y = -\frac{1}{4} \). Let's break it down step by step. ### Step 1: Rewrite the logarithmic condition Given: \[ \log_x y = -\frac{1}{4} \] This can be rewritten using the change of base formula: \[ \frac{\log y}{\log x} = -\frac{1}{4} \] From this, we can express \( \log y \) in terms of \( \log x \): \[ \log y = -\frac{1}{4} \log x \] ### Step 2: Substitute \( \log y \) in the expression We need to evaluate: \[ \log_x(xy^5) - \log_y\left(\frac{x^2}{\sqrt{y}}\right) \] First, let's break down \( \log_x(xy^5) \): \[ \log_x(xy^5) = \log_x x + \log_x y^5 = 1 + 5 \log_x y \] Substituting \( \log_x y = -\frac{1}{4} \): \[ \log_x(xy^5) = 1 + 5\left(-\frac{1}{4}\right) = 1 - \frac{5}{4} = 1 - 1.25 = -0.25 = -\frac{1}{4} \] ### Step 3: Evaluate \( \log_y\left(\frac{x^2}{\sqrt{y}}\right) \) Now, we evaluate: \[ \log_y\left(\frac{x^2}{\sqrt{y}}\right) = \log_y x^2 - \log_y \sqrt{y} \] Calculating each term: \[ \log_y x^2 = 2 \log_y x \] Using the change of base formula: \[ \log_y x = \frac{1}{\log_x y} = -4 \quad (\text{since } \log_x y = -\frac{1}{4}) \] Thus: \[ \log_y x^2 = 2(-4) = -8 \] Now, for \( \log_y \sqrt{y} \): \[ \log_y \sqrt{y} = \log_y y^{1/2} = \frac{1}{2} \] Putting it all together: \[ \log_y\left(\frac{x^2}{\sqrt{y}}\right) = -8 - \frac{1}{2} = -8.5 = -\frac{17}{2} \] ### Step 4: Combine the results Now we can combine the results: \[ \log_x(xy^5) - \log_y\left(\frac{x^2}{\sqrt{y}}\right) = -\frac{1}{4} - \left(-\frac{17}{2}\right) \] This simplifies to: \[ -\frac{1}{4} + \frac{17}{2} = -\frac{1}{4} + \frac{34}{4} = \frac{33}{4} \] ### Step 5: Identify \( p \) and \( q \) The expression evaluates to: \[ \frac{p}{q} = \frac{33}{4} \] Here, \( p = 33 \) and \( q = 4 \). ### Final Answer Since \( p \) and \( q \) are coprime, the value of \( q \) is: \[ \boxed{4} \]
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