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If x^({(3)/(4)("log"(3)x)^(2) + ("log"(3...

If `x^({(3)/(4)("log"_(3)x)^(2) + ("log"_(3)x)-(5)/(4)}) = sqrt(3)`, then x has

A

all integral values

B

two integral values and one irrational values

C

all irrational values

D

two rational values and an irrational value

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To solve the equation \( x^{\left(\frac{3}{4}(\log_3 x)^2 + \log_3 x - \frac{5}{4}\right)} = \sqrt{3} \), we will follow these steps: ### Step 1: Take logarithm on both sides We start by taking the logarithm (base 3) of both sides of the equation: \[ \log_3\left(x^{\left(\frac{3}{4}(\log_3 x)^2 + \log_3 x - \frac{5}{4}\right)}\right) = \log_3(\sqrt{3}) \] ### Step 2: Simplify the left side using the power rule of logarithms Using the property of logarithms that states \( \log_b(a^c) = c \cdot \log_b(a) \), we can simplify the left side: \[ \left(\frac{3}{4}(\log_3 x)^2 + \log_3 x - \frac{5}{4}\right) \cdot \log_3 x = \log_3(3^{1/2}) \] Since \( \log_3(\sqrt{3}) = \frac{1}{2} \). ### Step 3: Set up the equation Now we can write the equation as: \[ \left(\frac{3}{4}(\log_3 x)^2 + \log_3 x - \frac{5}{4}\right) \cdot \log_3 x = \frac{1}{2} \] ### Step 4: Let \( y = \log_3 x \) Let \( y = \log_3 x \). Then the equation becomes: \[ \frac{3}{4}y^2 + y - \frac{5}{4} = \frac{1}{2y} \] ### Step 5: Multiply through by \( 4y \) to eliminate the fraction Multiplying both sides by \( 4y \) gives: \[ 3y^3 + 4y^2 - 5y = 2 \] ### Step 6: Rearranging the equation Rearranging this gives us a cubic equation: \[ 3y^3 + 4y^2 - 5y - 2 = 0 \] ### Step 7: Use the Rational Root Theorem to find possible rational roots Testing \( y = 1 \): \[ 3(1)^3 + 4(1)^2 - 5(1) - 2 = 3 + 4 - 5 - 2 = 0 \] Thus, \( y = 1 \) is a root. ### Step 8: Perform polynomial long division Now we will divide \( 3y^3 + 4y^2 - 5y - 2 \) by \( y - 1 \): 1. Divide \( 3y^3 \) by \( y \) to get \( 3y^2 \). 2. Multiply \( 3y^2 \) by \( y - 1 \) to get \( 3y^3 - 3y^2 \). 3. Subtract to get \( 7y^2 - 5y - 2 \). 4. Divide \( 7y^2 \) by \( y \) to get \( 7y \). 5. Multiply \( 7y \) by \( y - 1 \) to get \( 7y^2 - 7y \). 6. Subtract to get \( 2y - 2 \). 7. Divide \( 2y \) by \( y \) to get \( 2 \). 8. Multiply \( 2 \) by \( y - 1 \) to get \( 2y - 2 \). 9. Subtract to get \( 0 \). Thus, we have: \[ 3y^3 + 4y^2 - 5y - 2 = (y - 1)(3y^2 + 7y + 2) \] ### Step 9: Solve the quadratic equation Now we need to solve \( 3y^2 + 7y + 2 = 0 \) using the quadratic formula: \[ y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{-7 \pm \sqrt{7^2 - 4 \cdot 3 \cdot 2}}{2 \cdot 3} \] \[ y = \frac{-7 \pm \sqrt{49 - 24}}{6} = \frac{-7 \pm \sqrt{25}}{6} = \frac{-7 \pm 5}{6} \] This gives us two solutions: 1. \( y = \frac{-2}{6} = -\frac{1}{3} \) 2. \( y = \frac{-12}{6} = -2 \) ### Step 10: Convert back to \( x \) Now we convert back to \( x \): 1. From \( y = 1 \): \( \log_3 x = 1 \) implies \( x = 3^1 = 3 \) 2. From \( y = -\frac{1}{3} \): \( \log_3 x = -\frac{1}{3} \) implies \( x = 3^{-\frac{1}{3}} = \frac{1}{\sqrt[3]{3}} \) 3. From \( y = -2 \): \( \log_3 x = -2 \) implies \( x = 3^{-2} = \frac{1}{9} \) ### Final Values of \( x \) Thus, the values of \( x \) are: - \( x = 3 \) (rational) - \( x = \frac{1}{\sqrt[3]{3}} \) (irrational) - \( x = \frac{1}{9} \) (rational) ### Conclusion The nature of the values of \( x \) is: - One rational value: \( 3 \) - One irrational value: \( \frac{1}{\sqrt[3]{3}} \) - One rational value: \( \frac{1}{9} \)

To solve the equation \( x^{\left(\frac{3}{4}(\log_3 x)^2 + \log_3 x - \frac{5}{4}\right)} = \sqrt{3} \), we will follow these steps: ### Step 1: Take logarithm on both sides We start by taking the logarithm (base 3) of both sides of the equation: \[ \log_3\left(x^{\left(\frac{3}{4}(\log_3 x)^2 + \log_3 x - \frac{5}{4}\right)}\right) = \log_3(\sqrt{3}) \] ...
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OBJECTIVE RD SHARMA ENGLISH-LOGARITHMS-Section I - Solved Mcqs
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