a: \(\left(3965-2378\right)-\left(437-1378\right)-528\)

\(=3965-2378-437+1378-528\)

\(=\left(3965-437-528\right)-\left(2378-1378\right)\)

\(=3000-1000=2000\)

b: \(\left(-457\right)+\left(-123\right)+23+237\)

\(=\left(-457+237\right)+\left(-123+23\right)\)

\(=-220-100=-320\)

c: \(\left(-329\right)-\left(15-101\right)-\left(25-440\right)\)

\(=-329-15+101-25+440\)

\(=\left(440-15-25\right)+\left(-329+101\right)\)

\(=400-228=172\)

Lời giải:

$=3965-2378-2378-437+1378-528$

$=3965-(2378-1378)-2378-437-528$

$=3965-1000-2378-437-528$

$=2965-(2378+437+528)=2965-3343=-378$

(3965-2378)-(437-1378)-528

=1587-(-941)-528

=1587+941-528

=2528-528

=2000

=2000 nha

HT

(3965-2378)-(437-1378)-528

=3965-2378-437-1378-528

=(3965-(437+528))-(2378-1378)

=3000-1000

=2000

Bài 1 :

\((3965-2378)-(437-1378)-528\)

\(=3965-2378-437+1378-528\)

\(=3965-(2378-1378)-(437+528)\)

\(=3965-1000-965\)

\(=(3965-965)-1000\)

\(=3000-1000\)

\(=2000\)

Bài 2 :

\((-x+31)-39=-69+11\)

\((-x+31)-39=-58\)

\(-x+31=-58+39\)

\(-x+31=-19\)

\(-x=-19-31\)

\(-x=-50\)

\(=>x=50\)

(-x+31)-39=-69+11

(-x+31)-39=-58

-x+31        =-58+39

-x+31        =-19

-x              =-19-31

-x              =-50

\(-\left(515-80+91\right)-\left(2003+80-91\right)\)

\(=-\left(515-80+91\right)-2003-80+91\)

Ta đơn giản còn:

\(=-515-2003\)

\(=-2518\)

Theo cách của mk nghĩ thuj nka!!!^_^

a) - ( 515 - 80 + 91 ) - ( 2003 + 80 - 91 )

=-526-1992=-2518

k nha YoonA

a) ( 1267-196 ) - ( 267 + 304 )

= ( 1267 - 267 ) - ( 196 + 304 )

= 1000 - 400

= 600

b ) ( 3965 - 2378 ) - ( 437-1378 ) - 528

=

a, (1267-196)-(267+304)

=(1267-267)-(196+304)

=1000-500

=500

b; (3965-2378)-(437-1378)-528

=(3965-528-437)-(2378-1378)

=3000-1000

=2000

cách 1

   - (515 - 80 + 91) - (2003 + 80 - 91)

= - ( 435 + 91 ) - ( 2083 - 91 )

= - 526 - 1992

=  - 2518

 - (515 - 80 + 91) - (2003 + 80 - 91)

= -515 + 80 - 91 - 2003 - 80 + 91

= -515 +( 80 - 80) + (90 - 90) -2003

= -515 + 0 + 0 -2003

= -2518

 - (515 - 80 + 91) - (2003 + 80 - 91)

= -515 + 80 - 91 - 2003 - 80 + 91

= -515 +( 80 - 80) + (90 - 90) -2003

= -515 + 0 + 0 -2003

= -2518