Bài 2;tính a, 1/5+(-1/3+9/5)+-7/6 b,(12/13+7)+(-8+1/13) c,(-4/5+2/3)+(-5/4+14/5)+(7/3-2) d,, -8+-3/5+7/10+9+-33/30 20/09/2021 Bởi Faith Bài 2;tính a, 1/5+(-1/3+9/5)+-7/6 b,(12/13+7)+(-8+1/13) c,(-4/5+2/3)+(-5/4+14/5)+(7/3-2) d,, -8+-3/5+7/10+9+-33/30
Đáp án: Giải thích các bước giải: `a, 1/5 + (-1/3 + 9/5 )+(-7/6)` `=1/5 + ([(-1).5]/3.5 + (3.9)/(3.5))-7/6` `=1/5 + [(-5)/15+27/15]- 7/6` `=1/5 + (27-5)/15 – 7/6` `=1/5 + 22/15 -7/6` `=3/15 + 22/15 – 7/6` `=25/15 -7/6` `=5/3 – 7/6` `= 10/6 – 7/6` `=3/6` `=1/2` `b, (12/13 +7)+(-8 + 1/13)` `= (12/13 +91/13) + (-104/13 +1/13)` `=103/13 + (-103)/13` `=0` `c, (-4/5 +2/3 )+(-5/4 +14/5)+(7/3-2)` `=(-12/15 + 10/15)+(-25/20 + 56/20 )+(7/3 – 6/3)` `=-2/15 + 31/20 + 1/3` `=-8/60 + 93/60 + 20/60` `=(-8+93+20)/60` `=105/60` `=7/4` `d, -8 + (-3)/5 + 7/10+9+(-33)/30` `=(-80)/10 + (-6)/10 + 7/10 + 90/10 + (-11)/10` `=(-80-6+7+90-11)/10` `=0/10` `=0` Bình luận
Đáp án: `↓↓↓` Giải thích các bước giải: `a)` `1/5+((-1)/3+9/5)+(-7)/6` `=1/5-1/3+9/5-7/6` `=(1/5+9/5)-(1/3+7/6)` `=2-3/2` `=1/2` `b)` `(12/13+7)+(-8+1/13)` `=12/13+7-8+1/13` `=(12/13+1/13)+(7-8)` `=1+(-1)` `=0` `c)` `(-4/5+2/3)+(-5/4+14/5)+(7/3-2)` `=(-4)/5+2/3-5/4+14/5+7/3-2` `=((-4)/5+14/5)+(2/3+7/3)-(5/4+2)` `=2+3-13/4` `=7/4` `d)` `(-8)+(-3)/5+7/10+9+(-33)/30` `=(-8)-3/5+7/10+9-33/30` `=(-8)-3/5+7/10+9-11/10` `=(-8+9)-3/5+(7/10-11/10)` `=1-3/5+(-2)/5` `=1-3/5-2/5` `=0` Bình luận
Đáp án:
Giải thích các bước giải:
`a, 1/5 + (-1/3 + 9/5 )+(-7/6)`
`=1/5 + ([(-1).5]/3.5 + (3.9)/(3.5))-7/6`
`=1/5 + [(-5)/15+27/15]- 7/6`
`=1/5 + (27-5)/15 – 7/6`
`=1/5 + 22/15 -7/6`
`=3/15 + 22/15 – 7/6`
`=25/15 -7/6`
`=5/3 – 7/6`
`= 10/6 – 7/6`
`=3/6`
`=1/2`
`b, (12/13 +7)+(-8 + 1/13)`
`= (12/13 +91/13) + (-104/13 +1/13)`
`=103/13 + (-103)/13`
`=0`
`c, (-4/5 +2/3 )+(-5/4 +14/5)+(7/3-2)`
`=(-12/15 + 10/15)+(-25/20 + 56/20 )+(7/3 – 6/3)`
`=-2/15 + 31/20 + 1/3`
`=-8/60 + 93/60 + 20/60`
`=(-8+93+20)/60`
`=105/60`
`=7/4`
`d, -8 + (-3)/5 + 7/10+9+(-33)/30`
`=(-80)/10 + (-6)/10 + 7/10 + 90/10 + (-11)/10`
`=(-80-6+7+90-11)/10`
`=0/10`
`=0`
Đáp án:
`↓↓↓`
Giải thích các bước giải:
`a)` `1/5+((-1)/3+9/5)+(-7)/6`
`=1/5-1/3+9/5-7/6`
`=(1/5+9/5)-(1/3+7/6)`
`=2-3/2`
`=1/2`
`b)` `(12/13+7)+(-8+1/13)`
`=12/13+7-8+1/13`
`=(12/13+1/13)+(7-8)`
`=1+(-1)`
`=0`
`c)` `(-4/5+2/3)+(-5/4+14/5)+(7/3-2)`
`=(-4)/5+2/3-5/4+14/5+7/3-2`
`=((-4)/5+14/5)+(2/3+7/3)-(5/4+2)`
`=2+3-13/4`
`=7/4`
`d)` `(-8)+(-3)/5+7/10+9+(-33)/30`
`=(-8)-3/5+7/10+9-33/30`
`=(-8)-3/5+7/10+9-11/10`
`=(-8+9)-3/5+(7/10-11/10)`
`=1-3/5+(-2)/5`
`=1-3/5-2/5`
`=0`