Hãy tính: \(36:\sqrt {{{2.3}^2}.18} - \sqrt {169}\).

* Hướng dẫn giải

 \((36:\sqrt {{{2.3}^2}.18} - \sqrt {169}\)

\( = 36:\sqrt {{{2.3}^2}.2.9} - \sqrt {{{13}^2}}\)

\(= 36:\sqrt {{{\left( {2.3.3} \right)}^2}} - \sqrt {{{13}^2}}\)

\(= 36:\left( {2.3.3} \right) - 13\)

= 2 - 13 =  - 11