\(-\dfrac{4}{5}.\dfrac{11}{13}+\dfrac{4}{5}.\left(-\dfrac{2}{13}\right)-\dfrac{1}{5}=\dfrac{4}{5}.\left(\dfrac{-11-2}{13}\right)-\dfrac{1}{5}=\dfrac{4}{5}.-1-\dfrac{1}{5}=-\dfrac{4}{5}-\dfrac{1}{5}=\dfrac{-4-1}{5}=-\dfrac{5}{5}=-1\)
Thực hiện phép tính:
1,-4/7 + 2/3x -9/14
2,17/13 - ( 4/13 - 11 )
3, 8 2/7 - ( 3 4/9 + 4 2/7 )
5, ( 2/3 - 1 1/2): 4/3 + 1/2
6, -5/13 + 2/5 + -8/13 + 3/5 - 3/7
7, 6/5 x 3/7 + 6/5 : 7/10 + 6/5
a) -5/11 + ( -6/11 + 1 )
b) -13/17 + ( 13/-21 + -4/17 )
c) -5/12 . 7/-17 . 9/-20
d) 13/17 . 4/-5 + 13/17 . -3/4
e) -5/7 . 2/11 + -5/7 . 9/11 + 5/7
f) -2/5 . (-6) + 3/4 . 4/-10
Bài 2: thực hiện phép tính bằng cách hợp lý
a. A=(1/2-7/13-1/3)+(-6/13+1/2+1và1/3)
b.B=0,75+2/5+(1/9-1và1/2+5/4)
c.(-5/9).3/11+(-13/18).3/11
d.(-2/3).3/11+(-16/9).3/11
e.(-1/4).(-2/13)-7/24.(-2/13)
f.(-1/27).3/7+(5/9).(-3/7)
g.(-1/5+3/7):2/11+(-4/5+4/7):2/11
tính a,13/17 . 5/11 -7/13 .5/11 .4/17 -2/5.6/13 b,1/2+1/3.1/4-1/5:1/6 so sánh n+2/n+3 và n+1/n+2
-1/9.15/22.-9/25
-2/7.(5/13-9/15)-2/7.8/13
3/10.(-4/9+2/5)-3/10.(5/9+-3/5)
4/11+-5/13+7/11+-8/13
Câu 13 : (-1/4 + 5/8 ) + -3/5
Câu 14 : M = 5/9 x 7/13 + 5/9 x 9/13 - 5/9 x 3/13
câu 15 : E = (-3/4 + 2/5) : 3/7 + (3/5 + -1/4) : 3/7
Câu 16 : H = 7/8 : (2/9 - 1/8) + 7/8 : (1/36 - 5/12)
3 phần 7 * 14 phần 5 - 1 phần 2
2 phần 5- 3 phần 5 * 5 phần 10
4 phần 13 * 5 phần 11 + 4 phần 13 * 6 phần 11 - 4 phần 13
4/7 +-5/8 - 3/28
-6/11: ( 3/5+4/11)
( 4/5 +1/2 ) : (3/13 -8/13)
(13+2/9 - 15+2/3).(302 - 54)
(18+3/7 - 17+1/4).(25-12.52)
x Y=
2/11+3/13+4/15+5/17
4+1/11+5/13+9/15+13/17
