Giải thích các bước giải:

Ta có:

\(\begin{array}{l}
1,\\
80 - \left[ {130 - {{\left( {12 - 4} \right)}^2}} \right] = 80 - \left[ {130 - {8^2}} \right]\\
 = 80 - \left[ {130 - 64} \right] = 80 - 66 = 14\\
2,\\
167 + \left[ {49 + {{\left( {13 - 8} \right)}^3}} \right] = 167 + \left[ {49 + {5^3}} \right]\\
 = 167 + \left[ {49 + 125} \right] = 167 + 174 = 341\\
3,\\
120 - \left[ {56 - {{\left( {9 - 4} \right)}^2}} \right] = 120 - \left[ {56 - {5^2}} \right]\\
 = 120 - \left[ {56 - 25} \right] = 120 - 31 = 89\\
4,\\
120 - \left[ {30 - {{\left( {5 - 1} \right)}^2}} \right] = 120 - \left[ {30 - {4^2}} \right]\\
 = 120 - \left[ {30 - 16} \right] = 120 - 14 = 106\\
5,\\
115 - 5.\left[ {70 - {{\left( {43 - 39} \right)}^3}} \right] = 115 - 5.\left[ {70 - {4^3}} \right]\\
 = 115 - 5.\left[ {70 - 64} \right] = 115 - 5.6 = 115 - 30 = 85\\
6,\\
247 + 3.\left[ {{{\left( {11 - {3^2}} \right)}^5} - {2^2}.3} \right] = 247 + 3.\left[ {{{\left( {11 - 9} \right)}^5} - 4.3} \right]\\
 = 247 + 3.\left[ {{2^5} - 12} \right] = 247 + 3.\left[ {32 - 12} \right] = 247 + 3.20 = 247 + 60 = 307\\
7,\\
\left[ {316 - {{\left( {25 - 19} \right)}^2}} \right]:56 + 19.5 = \left[ {316 - {6^2}} \right]:56 + 95\\
 = \left[ {316 - 36} \right]:56 + 95 = 280:56 + 95 = 5 + 95 = 100\\
8,\\
\left[ {243 - {{\left( {20 - 18} \right)}^3}} \right]:5 = \left[ {243 - {2^3}} \right]:5\\
 = \left[ {243 - 8} \right]:5 = 235:5 = 47\\
9,\\
\left[ {{3^{22}}.\left( {{3^8}:{3^3}} \right) + {{2.3}^{27}}} \right]:{3^{26}} = \left[ {{3^{22}}{{.3}^{8 - 3}} + {{2.3}^{27}}} \right]:{3^{26}}\\
 = \left[ {{3^{22}}{{.3}^5} + {{2.3}^{27}}} \right]:{3^{26}} = \left[ {{3^{22 + 5}} + {{2.3}^{27}}} \right]:{3^{26}}\\
 = \left[ {{3^{27}} + {{2.3}^{27}}} \right]:{3^{26}} = \left[ {{{3.3}^{27}}} \right]:{3^{26}} = {3^{1 + 27 - 26}} = {3^2} = 9\\
10,\\
\left[ {\left( {{3^5}{{.3}^8}} \right):{3^{11}} - {2^3}} \right] + 2018 = \left[ {{3^{5 + 8 - 11}} - {2^3}} \right] + 2018\\
 = \left[ {{3^2} - {2^3}} \right] + 2018 = \left( {9 - 8} \right) + 2018 = 1 + 2018 = 2019\\
11,\\
8697 - \left[ {{3^7}:{3^5} + 2.\left( {13 - 3} \right)} \right] = 8697 - \left[ {{3^{7 - 5}} + 2.10} \right]\\
 = 8697 - \left[ {{3^2} + 20} \right] = 8697 - 29 = 8668\\
12,\\
205 - \left[ {1200 - {{\left( {{4^2} - 2.3} \right)}^3}} \right]:40 = 205 - \left[ {1200 - {{\left( {16 - 6} \right)}^3}} \right]:40\\
 = 205 - \left[ {1200 - {{10}^3}} \right]:40 = 205 - 200:40 = 205 - 5 = 200
\end{array}\)