1: \(80-2\left[70-\left(12-4\right)^2\right]\)
\(=80-2\cdot\left[70-8^2\right]\)
\(=80-2\cdot\left(70-64\right)\)
\(=80-12=68\)
2: \(3^3\cdot8-\left[150-\left(10^2-8^2\right)\right]\)
\(=27\cdot8-150+100-64\)
\(=216-150+36\)
\(=252-150=102\)
3: \(115-5\left[70-\left(43-39\right)^3\right]\)
\(=115-5\left[70-4^3\right]\)
\(=115-5\cdot6=115-30=85\)
4: \(\dfrac{7^4}{7^2}+3^2\cdot2^3-2017^0\)
\(=7^2+8\cdot9-1\)
=49+72-1
=49+71
=120
9: \(1015-\dfrac{\left[\left(1014-1013\right)\cdot2+10\right]}{6}\)
\(=1015-\dfrac{1\cdot2+10}{6}\)
=1015-2
=1013
10: \(7+15:\left[55-2\cdot\left(36-11\right)\right]\)
\(=7+\dfrac{15}{55-2\cdot25}\)
\(=7+\dfrac{15}{55-50}\)
=7+15/5
=7+3
=10
11:
\(130-2\left[\dfrac{\left(60-45\right)}{3}+10\right]\)
\(=130-2\left[\dfrac{15}{3}+10\right]\)
=130-30
=100
12: \(\dfrac{720}{70+\left[284-\left(18+6^3\right)\right]}\)
\(=\dfrac{720}{70+284-18-216}\)
\(=\dfrac{720}{120}=6\)
