Can Impossible Inequalities Be Solved with Positive Real Numbers?

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The discussion introduces two new inequalities involving positive real numbers x, y, and z. The first inequality states that the sum of the reciprocals of x, y, and z is greater than or equal to a specific combination of their sums. The second inequality involves the squares of sums divided by their respective totals, asserting a relationship to the square root of the sums of x, y, and z. Participants clarify notation and confirm that these inequalities are proposed for all positive real numbers. The conversation emphasizes the need for precise mathematical expression in discussing these inequalities.
LAVRANOS
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To the impossible ineqaulity of another thread let me add two new ones
1)1/x +1/y +1/z >= 2/x+y + 2/y+z +2/z+x for x,y,z positive real Nos
2) (x+y)'/x+y+2z + (y+z)'/y+z+2x + (z+x)'/z+x+2y>= (sqrt(x)+ sqrt(y)+sqrt(z))'/3
where a' means a to the square and sqrt(x) means the sqaure root of x
 
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LAVRANOS said:
To the impossible ineqaulity of another thread let me add two new ones
1)1/x +1/y +1/z >= 2/x+y + 2/y+z +2/z+x for x,y,z positive real Nos
2) (x+y)'/x+y+2z + (y+z)'/y+z+2x + (z+x)'/z+x+2y>= (sqrt(x)+ sqrt(y)+sqrt(z))'/3
where a' means a to the square and sqrt(x) means the sqaure root of x
First clear up your notation: use parentheses and "^2" is standard for "square".

1)1/x+ 1/y+ 1/z>= 2/(x+y)+ 2/(y+z)+ 2/(z+ x)

2) (x+y)^2/(x+ y+ 2z)+ (y+z)^2/(y+ z+ 2x)+ (z+x)^2/(z+ x+ 2y)>= (sqrt(x)+ sqrt(y)+ sqrt(z))^2/3.

Now, are you asserting that these are identities for all positive real numbers or are they to be solved for specific x, y, z?
 
Sorry for the icovinience ,for all x,y,z belonging to real Nos that is the +VE ones
 
Inconvenience
 
I'll make it pretty.


\frac{1}{x}+\frac{1}{y}+\frac{1}{z} \geq \frac{2}{x+y}+\frac{2}{y+z}+\frac{2}{x+z}

\forall x, y, z \in \mathbb{R}_+

and

\frac{(x+y)^2}{x+y+2z}+\frac{(y+z)^2}{2x+y+z}+\frac{(x+z)^2}{x+2y+z}\geq (\sqrt{x} +\sqrt{y} +\sqrt{z})^{\frac{2}{3}}

I think again \forall x, y, z \in \mathbb{R}_+
 
(x+y)^2/x+y+2z +(y+z)^2/y+z+2x +(z+x)^2/z+x+2y>= (sqrt(x) +sqrt(y)+sqrt(z))^2/3
it is sqrt(x) +sqrt(y)+sqrt(z) all to the square and all that divided by 3
THANKS DIFFY
 
\frac{1}{x}+\frac{1}{y}+\frac{1}{z} \geq \frac{2}{x+y}+\frac{2}{y+z}+\frac{2}{x+z}

\forall x, y, z \in \mathbb{R}_+

and

\forall x, y, z \in \mathbb{R}_+
\frac{(x+y)^2}{x+y+2z}+\frac{(y+z)^2}{2x+y+z}+\frac{(x+z)^2}{x+2y+z}\geq \frac{(\sqrt{x} +\sqrt{y} +\sqrt{z})^{2}}{3}
 

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