a)25+(-13+8)

=25+(-5)=20

b)7+(-12+43)-[2+(19-34)]

=7+31-[2+(-15)]

=7+31-(-13)

=25

a)25-13+8=20

b)7-12+43-2+19-34=21

a) 25-13+8=20

b)7-12+43-2-19+34=51

a) 25 + ( - 13 + 8 )

= 25 + (-5)

= 20

b) 7 + ( - 12 + 43 ) - [ 2 + ( 19 - 34)]

= 7 + (-12 + 43 ) - [ 2 + (-15) ]

= 7 + 31 - (-13)

= 7 + 31 + 13

= 38 + 13

= 51

Mình trước nhất mà !!!

gioi that do

a ) = 20

b ) = 53

a) =25-13+8=20

b) =7-12+43-(2+19-34)=38+13=51

a) 25 + ( - 13 + 8 )

= 25 - 13 + 8

= 20

b) 7 + ( - 12 + 43 ) - [ 2 + ( 19 - 34 ) ]

= 7 - 12 + 43 - [ 2+ 19 - 34 ]

= - 5 + 43 - 2 - 19 + 34

= 61

\(25+\left(-13+8\right)\)

\(=25-13+8\)

\(=12+8\)

\(=20\)

\(7+\left(-12+43\right)-\left[2+\left(19-34\right)\right]\)

\(=7-12+43-\left[2+19-34\right]\)

\(=7-12+43-2-19+34\)

\(51\)

a)25+(-13+8)

=25+(-13)+8

=12+8

=20

b)7+(-12+43)+[2+(19-34)]

=7+(-12)+43+2+(-15)

=(-5)+43+2+(-15)

=38+2+(-15)

=40+(-15)

=25

nhớ tick cho mình nha!

\(a.7+\left(-12+43\right)-\left[2+\left(19-34\right)\right]\)

\(=7+31-\left[2+\left(-15\right)\right]\)

\(=7+31-\left(-13\right)\)

\(=38-\left(-13\right)\)

\(=51\)

\(b.25+\left(-13+8\right)\)

\(=25+\left(-5\right)\)

\(=20\)

\(c.\left(-8\right)-\text{ }\left[\left(-4\right)+6\right]\)

\(=\left(-8\right)-2\)

\(=\left(-10\right)\)

\(d.\left(-8\right)+4-6\)

\(=\left(-4\right)-6\)

\(=\left(-10\right)\)

áp dụng kiến thức tính nhanh ý

1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275

= 1275