a) 1125 – ( 374 + 1125) + (-65 +374) b) -23 . 63 + 23 . 21 – 58 . 23
c) -2003 + (-21+75 + 2003) d) 942 – 2567 + 2563 – 1942
e) 12 – 12 + 11 + 10 – 9 + 8 – 7 + 5 – 4 + 3 + 2 -1
hộ em vs em đg cần gấp ạ!!
a) 1125 – ( 374 + 1125) + (-65 +374) b) -23 . 63 + 23 . 21 – 58 . 23 c) -2003 + (-21+75 + 2003) d) 942 – 2567 + 2563 –
By Emery
Đáp án + Giải thích các bước giải:
`a//1125-(374+1125)+(-65+374)`
`=1125-374-1125-65+374`
`=(1125-1125)+(374-374)-65`
`=0+0-65`
`=-65`
`b//-23.63+23.21-58.23`
`=23.(-63)+23.21-58.23`
`=23.(-63+21-58)`
`=23.(-100)`
`=-2300`
`c//-2003+(-21+75+2003)`
`=-2003-21+75+2003`
`=(2003-2003)+(75-21)`
`=0+54`
`=54`
`d//942-2567+2563-1942`
`=(942-1942)+(2563-2563)-4`
`=-1000+0-4`
`=-1004`
`e//12-12+11+10-9+8-7+5-4+3+2-1`
`=(12-12)+(10-9)+(8-7)+(5-4)+(2-1)+(11+3)`
`=0+1+1+1+1+14`
`=18`
Đáp án:
\(a)\,\,1125 – ( 374 + 1125) + (-65 +374)\\=1125-374-1125-65+374\\=(1125-1125)+(-374+374)-65\\=-65\\b)\,\,-23 . 63 + 23 . 21 – 58 . 23\\=23.(-63+21-58)\\=23.(-100)\\=-2300\\c)\,\,-2003 + (-21+75 + 2003)\\=-2003-21+75+2003\\=(-2003+2003)+(-21+75)\\=54\\d)\,\,942 – 2567 + 2563 – 1942\\=(942-1942)+(-2567+2563)\\=-1000-4\\=-1004\\e)\,\,12 – 12 + 11 + 10 – 9 + 8 – 7 + 5 – 4 + 3 + 2 -1\\=(12-12)+(11-1)+(10-9)+(8-7)+(5-4)+(3+2)\\=0+10+1+1+1+5\\=18\)