irrational/rational numbers: Is -1/sqrt[36] irrational?

[spicytakoyum]

is -1 over the square root of 36 irrational?

 

[pka]

Absolutely NOT!
\(\displaystyle \sqrt {36} = 6\) is rational.
The rationals are closed with respect to field operations.

 

[arthur ohlsten]

A rational number is any number that can be written as a ratio of integers.
example. Is 7.456 a rational number? rewrite it as a fraction of integers.

7456
--------
1000

7.456 is rational

Arthur