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Interesting Algebra Question

Note by Saran Balachandar
2 years ago

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  Easy Math Editor

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*italics* or _italics_ italics
**bold** or __bold__ bold

- bulleted
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  • bulleted
  • list

1. numbered
2. list

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Note: you must add a full line of space before and after lists for them to show up correctly
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[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
    # 4 spaces, and now they show
    # up as a code block.

    print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears as
Remember to wrap math in \( ... \) or \[ ... \] to ensure proper formatting.
2 \times 3 \( 2 \times 3 \)
2^{34} \( 2^{34} \)
a_{i-1} \( a_{i-1} \)
\frac{2}{3} \( \frac{2}{3} \)
\sqrt{2} \( \sqrt{2} \)
\sum_{i=1}^3 \( \sum_{i=1}^3 \)
\sin \theta \( \sin \theta \)
\boxed{123} \( \boxed{123} \)

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Using the first equation and AM - GM inequality, we have

\( \frac{a+b}{2} \geq \sqrt{ab} \)

\( 4 \geq ab \)

From the second eq.

\( c^2 - 2\sqrt{3}c + 3 = \frac{ab}{2}- 2 \)

\( (c - \sqrt{3})^2 = \frac{ab}{2} - 2 \)

Since the left side is a square and thus positive, the right side must be positive, that is we must have \( \frac{ab}{2} \geq 2 \implies ab \geq 4 \)

Therefore, we see that \( ab = 4 \). Which implies \( a = b = 2 \) and \( c = \sqrt{3} \)

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Comment deleted Oct 03, 2016

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Try the wiki.

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