Bài 1:
a,1020 : [ 86 - (47.14 - 640)]
=1020 : [ 86 - (658 -640)]
=1020 : ( 86 - 18)
=1020 : 68
=15
b,56:5³+2³.2²+(2005.4³)0
=5³-25+1
=125+32+1
=158
c, 80 - (4.5²-3.2³)
=80 - (4.25-3.8)
=80 - (100-24)
=80 - 76
=4
d, 2².3-(110-8-012):3²
=4.3-(1-8-0):9
=12-9:9
=12-1
=11
e,145:14³-(16.2³-16.2²)
=14²-[16.(2³-2²)]
=196-16.(8-4)
=196-16.4
=196-64
=132
g,425+24.371-371.14-25
=425+371.(24-14)-25
=425+371.10-25
=425+3710-25
=400+3710
=4110
Bài 2:
a,7².234+8².51-7².170
=7².(234-170)+8².51
=49.64+64.51
=64(49+51)
=64.100
=6400
b,56:54+125-|-75|
=5²+(125-75)
=25+50
=75
c,175-75:(355-11.32)
=175-75:(355-352)
=175-75:3
=175-25
=150
Nhớ cho mk CTLHN nhé ^^
