A = \(\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)

\(=3,1-2,5+2,5-3,1=6,2\)

B = \(\left(5,3-2,8\right)-\left(4+5,3\right)\)

\(=5,3-2,8-4-5,3=-6,8\)

C = \(-\left(251.3+281\right)+3.251-\left(1-281\right)\)

\(=-251.3-281+3.251-1+281=-1\)

D = \(-\left(\frac{3}{5}+\frac{3}{4}\right)-\left(-\frac{3}{4}+\frac{2}{5}\right)\)

\(=-\frac{3}{5}-\frac{3}{4}+\frac{3}{4}-\frac{2}{5}=-1\)

(Nhớ k cho mình với nhá!)

\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)

\(A=3,1-2,5+2,5-3,1\)

\(A=\left(3,1-3,1\right)-\left(2,5-2,5\right)\)

\(A=0-0\)

\(A=0\)

\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\)

\(B=5,3-2,8-4-5,3\)

\(B=\left(5,3-5,3\right)-\left(2,8+4\right)\\ B=0-6,8\\ B=-6,8\)

Tính giá trị:

\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\\ A=3,1-2,5+2,5-3,1\\ A=\left(3,1-3,1\right)-\left(2,5-2,5\right)\\ A=0\)

\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\\ B=5,3-2,8-4-5,3\\ B=\left(5,3-5,3\right)-\left(2,8+4\right)\\ B=-6,8\)

\(C=-\left(251.3\right)+281+3.251-\left(1-281\right)\)

\(C=\left[-\left(251.3\right)+3.251\right]+\left[281-\left(1-281\right)\right]\\ C=0+560\\ C=560\)

\(D=-\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(-\dfrac{3}{4}+\dfrac{2}{5}\right)\\ D=-\dfrac{3}{5}-\dfrac{3}{4}+\dfrac{3}{4}-\dfrac{2}{5}\\ D=\left(-\dfrac{3}{5}-\dfrac{2}{5}\right)+\left(-\dfrac{3}{4}+\dfrac{3}{4}\right)\\ D=-1+0\\ D=-1\)

A = (3,1 – 2,5)  – (-2,5 + 3,1) = 3,1 – 2,5 + 2,5 – 3,1 = 0

B  = (5,3 – 2,8) – (4 + 5,3) = 5,3 – 2,8 – 4 – 5,3

A=(3,1-2,5)-(-2,5+3,1)=3,1-2,5+2,5-3,1=0

B=(5,3-2,8)-(4+5,3)=5,3-2,8-4-5,3=-6,8

= -251 . 3 - 281 + 3 . 251 - 1 + 281

ấn nhầm

a) (4,1 - 2,5 ) - ( -2,5 + 3,1 ) = 1,6 - 0,6 = 1

b) ( 5,3 - 2,8) - ( 4+ 5,3) = 2,5 - 9,3 = -6.8

c) -( 251,3 + 281) + 3,251 - (1 - 981) = -532,3 + 3,251 + 980 = 450,951

d) -(3/5 + 3/4) - ( -3/4 +2/5) = -3/5 - 3/4 + 3/4 - 2/5 = -1

\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)

\(=3,1-2,5+2,5-3,1=0\)

\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\)

\(=5,3-2,8-4-5,3=-6,8\)

\(C=-\left(251.3+281\right)+3.215-\left(1-281\right)\)

\(=-753-281+645-1+281\)

\(=-753+654-1=-100\)

\(D=-\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(\dfrac{-3}{4}+\dfrac{2}{5}\right)\)

\(=-\dfrac{3}{5}-\dfrac{3}{4}+\dfrac{3}{4}-\dfrac{2}{5}=\dfrac{-3}{5}-\dfrac{2}{5}=-1\)

\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)

\(=3,1-2,5+2,5-3,1\)

\(=\left(3,1-3,1\right)-\left(2,5-2,5\right)\)

\(=0\)

Vậy \(A=0.\)

\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\)

\(=5,3-2,8-4-5,3\)

\(=\left(5,3-5,3\right)-\left(2,8+4\right)\)

\(=-\dfrac{34}{5}\)

Vậy \(B=\dfrac{-34}{5}.\)

\(C=-\left(251.3+281\right)+3.215-\left(1-281\right)\)

\(=-251.3-281+3.215-1+281\)

\(=-753-\left(281-281\right)+645\)

\(=-753+645=-108\)

Vậy \(C=-108.\)

\(D=-\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(-\dfrac{3}{4}+\dfrac{2}{5}\right)\)

\(=-\dfrac{3}{5}-\dfrac{3}{4}+\dfrac{3}{4}-\dfrac{2}{5}\)

\(=\left(\dfrac{-3}{5}-\dfrac{2}{5}\right)-\left(\dfrac{3}{4}-\dfrac{3}{4}\right)\)

\(=-1\)

Vậy D = -1.

A=(3,1-2,5)-(-2,5+3,1)
A=3,1-2,5=2,5-3,1

A=(3,1-3,1)+(2,5-2,50

A=0

B=(5,3-2,8)-(4+5,3)

B=5,3-2,8-4-5,3

B=(5,3-5,3)-(4+2,8)

B=0-6,8

B=-6,8

C=-(251.3+281)+3.215-(1-281)

C=-251.3-281+3.215-1+281

C=3(-251+215)-(281+281)-1

C=-108-1

C=-109
D=\(-\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(-\dfrac{3}{4}\right)+\dfrac{2}{5}\)
\(D=-\dfrac{3}{5}+-\dfrac{3}{4}+\dfrac{3}{4}+\dfrac{2}{5}\)

D=\(\left(-\dfrac{3}{5}+\dfrac{2}{5}\right)+\left(-\dfrac{3}{4}+\dfrac{3}{4}\right)\)

\(D=\dfrac{-1}{5}\)

1a, (-3,8) + [ (-5,7)+3,8]

= (-3,8+3,8) -5,7

= -5,7

b, 31,4 +[6,4 +(-18)]

= 31,4 - 11,6

= 19,8

c,[(9,6 )+4,5 ] +[9,6 +(-1,5)]

= 9,6 +9,6 +(4,5-1,5)

= 19,2 +3

=22,2

d, [ (-4,9) + (-7,8)] +[1,9+2,8]

= (-4,9 +1,9)+ (-7,8+2,8)

= -3 -5

=-8

e, (3,1-2,5)-(-2,5+3,1)

= (3,1-3,1)+(2,5-2,5)

=0

f, (5,3 -2,8 )- (4+5,3)

= (5,3-5,3) -2,8-4

= -6,8

g, -(251,3 +281 )+ 3,251 -(1-281)

= -251,3-281+3,251 -1+281

= (-281+281) -251,3 +3,251 -1

= -249,049

h,-(3/54+3/4)-(-3/4 +2/5)

= -3/54-3/4 +3/4 +2/5

=(-3/4+3/4) -3/54 +2/5

=123/270

chúc bạn học tốt

lấy mt bấm phắt là ra

C = - (251.3 + 281) + 3.251 – (1- 281)

= -251.3 -281 + 251.3 -1 + 281

= (-251.3 + 251.3 )+ ( -281 + 281) -1

= 0 + 0 - 1 = -1.