MHB Is the Inequality of Series Proven with 1 to 99 and 2 to 100?

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The discussion centers on proving the inequality between the product of odd numbers from 1 to 99 and the product of even numbers from 2 to 100. The goal is to show that the ratio of these products is greater than 1/(10√2). Participants engage in mathematical reasoning and calculations to establish this inequality. The conversation highlights the significance of understanding series and products in mathematical proofs. The conclusion emphasizes the validity of the inequality as a key mathematical result.
Albert1
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prove :
$\dfrac {1\times 3 \times 5\times------\times 99}{2\times 4\times 6\times --\times {100}}>\dfrac {1}{10\sqrt 2}$
 
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Albert said:
prove :
$\dfrac {1\times 3 \times 5\times------\times 99}{2\times 4\times 6\times --\times {100}}>\dfrac {1}{10\sqrt 2}$
Let

$A= \frac{3}{4}*\frac{5}{6}\cdots\frac{99}{100}$
$B = \frac{2}{3}*\frac{4}{5}\cdots\frac{98}{99}$
In the above products each term of A is > B pairwise so A > B

$A * B = \frac{2}{100}$ and hence $A \gt\sqrt{(\frac{2}{100})}$

hence $ A \gt\frac{\sqrt{2}}{10}$

hence given expression which is $\frac{A}{ 2}$

so $\gt\dfrac{1}{10\sqrt{2}}$
 
kaliprasad said:
Let

$A= \frac{3}{4}*\frac{5}{6}\cdots\frac{99}{100}$
$B = \frac{2}{3}*\frac{4}{5}\cdots\frac{98}{99}$
In the above products each term of A is > B pairwise so A > B

$A * B = \frac{2}{100}$ and hence $A \gt\sqrt{(\frac{2}{100})}$

hence $ A \gt\frac{\sqrt{2}}{10}$

hence given expression which is $\frac{A}{ 2}$

so $\gt\dfrac{1}{10\sqrt{2}}$
very nice !
 
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