Interval

X^2<5

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Math	Appears 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}`	$\frac{2}{3}$
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`\sum_{i=1}^3`	$\sum_{i=1}^3$
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`\boxed{123}`	$\boxed{123}$

Comments

$x^2 < 5 \rightarrow x^2 - 5 < 0$

$\Delta = 0^2 -4 \cdot -5 \cdot 1 = 20$

$x= \frac{0 \pm \sqrt20}{2}$

$x_1 = \frac{2\sqrt5}{2} = \sqrt5$

$x_2 = \frac{-2\sqrt5}{2} = -\sqrt5$

( $x \in\mathbb{R} / -\sqrt5< x < \sqrt5$ )

Gabriel Merces - 7 years, 7 months ago

x<(5)^1/2

shaheed vh - 7 years, 7 months ago

Not necessarily. There's more to it.

Daniel Leong - 7 years, 7 months ago

Math	Appears 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}`	$\boxed{123}$