A brain teaser

How can we construct 1 by using numbers from 0 to 9 exactly once and not using 0 as index ?

#HelpMe!

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`italics` or `_italics_`	italics
`bold` or `__bold__`	bold
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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}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

I just found a solution by a little bit of trial and error : $(-9+8+7-6+5-3+2)/4 + 0/1$

A Former Brilliant Member - 7 years, 7 months ago

Questions: What is "index"? What are the allowed operations/functions? Are we allowed to use brackets? Are we allowed to rearrange the numbers (seems so)? Are we allowed to concatenate numbers?

Ivan Koswara - 7 years, 7 months ago

That's not given in the question!!!

Tanuj Sur - 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}`	$\boxed{123}$