Can This Algebraic Inequality Be Proven Using AM-GM and GM-HM Methods?

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In summary, using the AM-GM and GM-HM inequalities, it can be proven that $(1+\dfrac {a}{b})(1+\dfrac {b}{c})(1+\dfrac {c}{a})\geq 2(1+\dfrac {a+b+c}{\sqrt[3]{abc}})$ for any positive values of a, b, and c.
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Albert1
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a,b,c >0 , prove that :

$(1+\dfrac {a}{b})(1+\dfrac {b}{c})(1+\dfrac {c}{a})\geq 2(1+\dfrac {a+b+c}{\sqrt[3]{abc}})$
 
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Re: Prove an inequality

Albert said:
a,b,c >0 , prove that :
$(1+\dfrac {a}{b})(1+\dfrac {b}{c})(1+\dfrac {c}{a})\geq 2(1+\dfrac {a+b+c}{\sqrt[3]{abc}})$
using the AM-GM inequality for left side
expansion of left side =$2+k=2+\dfrac{k}{3}+\dfrac {2k}{3}\geq 4+\dfrac {2k}{3}$
where $k=\dfrac {b}{a} +\dfrac{a}{b}+\dfrac{c}{b} +\dfrac{b}{c}+\dfrac{a}{c} +\dfrac{c}{a}\geq 6 $
using the GM-HM inequality for right side
right side :$\leq 2(1+\dfrac {(a+b+c)}{\dfrac {3}{(1/a) + (1/b) + (1/c)}} =
2(1+\dfrac {(a+b+c)\times \left [(1/a) + (1/b) + (1/c)\right ]}{3} )=4+\dfrac {2k}{3}$
$\therefore $ the proof is done
 
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FAQ: Can This Algebraic Inequality Be Proven Using AM-GM and GM-HM Methods?

What does it mean to "prove an inequality"?

Proving an inequality means to show that one mathematical expression is greater than, less than, or not equal to another expression. This is done by using logical reasoning and mathematical operations to demonstrate the relationship between the two expressions.

Why is it important to prove inequalities?

Proving inequalities is important because it allows us to make accurate comparisons between different quantities or variables. It also helps us understand the relationships between different mathematical expressions and can be used to solve real-world problems.

What are the different methods for proving inequalities?

There are several methods for proving inequalities, including algebraic manipulation, using properties of inequalities, and using mathematical induction. Which method is most appropriate will depend on the specific inequality being proven.

Can inequalities be proven in more than one way?

Yes, there are often multiple ways to prove an inequality. Some methods may be more efficient or elegant than others, but as long as the logical reasoning is sound, any valid proof method can be used.

Are there any common mistakes to avoid when proving inequalities?

One common mistake when proving inequalities is assuming the inequality holds true for all values without considering any exceptions. It is important to check for any values or cases that may make the inequality invalid. It is also important to clearly explain each step of the proof and use proper notation to avoid confusion.

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