# A brain teaser

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

Note by Tanuj Sur
4 years, 7 months ago

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold
- bulleted- list
• bulleted
• list
1. numbered2. list
1. numbered
2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1paragraph 2

paragraph 1

paragraph 2

[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} $$\boxed{123}$$

Sort by:

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

- 4 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?

- 4 years, 7 months ago

That's not given in the question!!!

- 4 years, 7 months ago