Explicație pas cu pas:
20)
a)
[tex]13 + ( - 78) \div 6 = 13 + ( - 78 \div 6) \\ = 13 + ( - 13) = 13 - 13 = 0 \\ [/tex]
b)
[tex]\{3 - 2\cdot \left[5 - \left( - 2 \right)^{3} \div 4 - 5\cdot3 \right]\}\cdot(-10)^{2} = \\ = \left[3 - 2\left(5 + 8 \div 4 - 15\right) \right]\cdot100 = \left[3 - 2\left(5 + 2 - 15\right) \right]\cdot100 \\ = \left[3 - 2\left( - 8\right) \right]\cdot100 = (3 + 16)\cdot100 = 19\cdot100 = 1900[/tex]
