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If 3a+(1)/(3a) = 2sqrt3 , evaluate: ...

If ` 3a+(1)/(3a) = 2sqrt3` , evaluate:
` 3a- (1)/(3a)`

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To solve the equation \( 3a + \frac{1}{3a} = 2\sqrt{3} \) and evaluate \( 3a - \frac{1}{3a} \), we can follow these steps: ### Step 1: Set up the equation We start with the given equation: \[ 3a + \frac{1}{3a} = 2\sqrt{3} \] ### Step 2: Use the identity We will use the identity: \[ (a - b)^2 = (a + b)^2 - 4ab \] Here, let \( a = 3a \) and \( b = \frac{1}{3a} \). ### Step 3: Calculate \( (3a - \frac{1}{3a})^2 \) Using the identity: \[ (3a - \frac{1}{3a})^2 = (3a + \frac{1}{3a})^2 - 4 \cdot 3a \cdot \frac{1}{3a} \] ### Step 4: Substitute the known value We know \( 3a + \frac{1}{3a} = 2\sqrt{3} \), so we can substitute this into the equation: \[ (3a - \frac{1}{3a})^2 = (2\sqrt{3})^2 - 4 \] ### Step 5: Calculate \( (2\sqrt{3})^2 \) Calculating \( (2\sqrt{3})^2 \): \[ (2\sqrt{3})^2 = 4 \cdot 3 = 12 \] ### Step 6: Substitute back into the equation Now substituting back: \[ (3a - \frac{1}{3a})^2 = 12 - 4 \] \[ (3a - \frac{1}{3a})^2 = 8 \] ### Step 7: Take the square root Now we take the square root of both sides: \[ 3a - \frac{1}{3a} = \sqrt{8} \] \[ 3a - \frac{1}{3a} = 2\sqrt{2} \] ### Final Answer Thus, the value of \( 3a - \frac{1}{3a} \) is: \[ \boxed{2\sqrt{2}} \]
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  11. If 3a+(1)/(3a) = 2sqrt3 , evaluate: 3a- (1)/(3a)

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  12. If 3a+(1)/(3a) = 2sqrt3 , evaluate: 9a^(2) +(1)/( 9a^(2))

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  13. If 3a+(1)/(3a) = 2sqrt3 , evaluate: 81 a^(4) + (1)/(81a^(4))

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