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If a, b, c are positive integers, then ...

If a, b, c are positive integers, then
`((a^(2)+b^(2)+c^(2))/(a+b+c))^(a+b+c)gta^(x)b^(y)c^(z)`, then

A

`x=a, y=b, z=c`

B

`x=b, y=a, z=c`

C

`x=(1)/(a),y=(1)/(b),z=(1)/( c )`

D

`x=y=z=1`

Text Solution

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The correct Answer is:
To solve the inequality \(\left(\frac{a^2 + b^2 + c^2}{a + b + c}\right)^{(a + b + c)} > a^x b^y c^z\) for positive integers \(a\), \(b\), and \(c\), we will use the concept of weighted arithmetic mean and weighted geometric mean. ### Step-by-step Solution: 1. **Understanding Weighted Means**: - The weighted arithmetic mean (WAM) of \(a\), \(b\), and \(c\) with weights \(a\), \(b\), and \(c\) respectively is given by: \[ \text{WAM} = \frac{a \cdot a + b \cdot b + c \cdot c}{a + b + c} = \frac{a^2 + b^2 + c^2}{a + b + c} \] - The weighted geometric mean (WGM) is given by: \[ \text{WGM} = \left(a^a b^b c^c\right)^{\frac{1}{a + b + c}} \] 2. **Applying the Inequality**: - By the property of weighted means, we know that: \[ \text{WAM} \geq \text{WGM} \] - Thus, we can write: \[ \frac{a^2 + b^2 + c^2}{a + b + c} \geq \left(a^a b^b c^c\right)^{\frac{1}{a + b + c}} \] 3. **Raising Both Sides to the Power of \(a + b + c\)**: - Raising both sides of the inequality to the power of \(a + b + c\) gives: \[ \left(\frac{a^2 + b^2 + c^2}{a + b + c}\right)^{(a + b + c)} \geq a^a b^b c^c \] 4. **Comparing with the Given Expression**: - The inequality we need to satisfy is: \[ \left(\frac{a^2 + b^2 + c^2}{a + b + c}\right)^{(a + b + c)} > a^x b^y c^z \] - From the previous step, we have: \[ a^a b^b c^c \geq a^x b^y c^z \] 5. **Identifying Values of \(x\), \(y\), and \(z\)**: - To satisfy the inequality \(a^a b^b c^c \geq a^x b^y c^z\), we can compare the exponents: - This leads to: - \(x \leq a\) - \(y \leq b\) - \(z \leq c\) - The maximum values that satisfy this are: - \(x = a\) - \(y = b\) - \(z = c\) ### Conclusion: Thus, the values of \(x\), \(y\), and \(z\) are: \[ \boxed{x = a, \; y = b, \; z = c} \]

To solve the inequality \(\left(\frac{a^2 + b^2 + c^2}{a + b + c}\right)^{(a + b + c)} > a^x b^y c^z\) for positive integers \(a\), \(b\), and \(c\), we will use the concept of weighted arithmetic mean and weighted geometric mean. ### Step-by-step Solution: 1. **Understanding Weighted Means**: - The weighted arithmetic mean (WAM) of \(a\), \(b\), and \(c\) with weights \(a\), \(b\), and \(c\) respectively is given by: \[ \text{WAM} = \frac{a \cdot a + b \cdot b + c \cdot c}{a + b + c} = \frac{a^2 + b^2 + c^2}{a + b + c} ...
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