Thực hiện phép tính:
a) \({3.5^2} - 16:{2^2}\) b) \({2^3}.17 - {2^3}.14\)
c) 15.141 + 59.15 d) 17.85 + 15.17 – 120
e) \(20 - \left[ {30 - {{\left( {5 - 1} \right)}^2}} \right]\)
a) \({3.5^2} - 16:{2^2} = 3.25-16:4 = 75-4 = 71\)
b) \({2^3}.17 - {2^3}.14 = 8.17-{\rm{ }}8.14{\rm{ }} = 8\left( {17 - 14} \right)\)
= 8.3 = 24
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c) 15.141 + 59.15 = 15.(141+59) =15.200 = 3000
d) 17.85 + 15.17 – 120 = 17.(85+15) -120
= 17.100 – 120 = 1700 – 120 = 1580
e) \(20 - \left[ {30 - {{\left( {5 - 1} \right)}^2}} \right]\)
= 20 - (30 - \({4^2})\)
= 20 - (30 - 16)
= 20 – 14 = 6