= 0

= 2004

(-404)+1002+(-2000)+1998+(-596)

=[1002+1998+(-2000)]+[(-404)+(-596)]

= 0+0=0

126+(-20)+2004+(-106)

={126+[(-20)+(-106)]+2004

=0 + 2004 =2004

a) (-137)+254+(-270)+(-463)+246

=[(-137)+(-463)]+(254+246)+(-270)

=(-600)+500+(-270)

=(-100)+(-270)

=-370

b)(-596)+1998+1002+(-404)+197

=[(-596)+(-404)]+(1998+1002)+197

=(-1000)+3000+197

=2000+197

==2197

Đúng thì tick nha

a,-136+123+(-264)+(-83)+240

= (123 - 83) - (136 + 264) + 240

= -40 - 400 + 240

= (240 - 40) - 400

= 200 - 400 = -200

b,-596+2001+1999+(-404)+189

= (2001 + 1999) - (596 + 404) + 189

= 4000 - 1000 + 189

= 3000 + 189

= 3189

a) ( - 30 ) + ( - 29 ) + ( - 28 ) + ... + 48 + 49 + 50

= [ ( - 30 ) + 30 ] + [ ( - 29 )  + 29 ] + [ ( - 28 ) + 28 ] + ..... + 48 + 49 + 50

= 0 + 0 + 0 + .... + 31 + 32 + 33 + 34 + 35 + 36 + 37 + 38 + 39 + 40 + 41 + 42 + 43 + 44 + 45 + 46 + 47 + 48 + 49 + 50

=  31 + 32 + 33 + 34 + 35 + 36 + 37 + 38 + 39 + 40 + 41 + 42 + 43 + 44 + 45 + 46 + 47 + 48 + 49 + 50

= ( 31 + 49 ) + ( 32 + 48 ) + ( 33 + 47 ) + ( 34 + 46 ) + ( 35 + 45 ) + ( 36 + 44 ) + ( 37 + 43 ) + ( 38 + 42 ) + ( 39 + 41 ) + 50

= 80 + 80 + 80 + 80 + 80 + 80 + 80 + 80 + 80 + 50

= 80 . 9 + 50

= 720 + 50

= 770

c) - 34 + 54 - ( 157 + 43 ) = - 180

d ) 1+ 99 -(2 + 98) + 3 + 97 - (4 + 96) + .....+ (- 100 ) = - 100

a) 154 + 46 - ( 12 + 88 ) = 100

b) 2011 + 1989 - ( 596 + 404 ) = 3000

1

a)1000-570-430+234

=1000-(570+430)+234

=1000-1000+234

=0+234

=234

b)-596+2001+1999-404+189

=2001+(1999-596-404)+189

= 2001+[1999-(596+404)+189

=2001+(1999-1000)+189

=2001+999+189

=3000+189

=3189                       

2

S1=1+(-3)+5+(-7)+...+17

=1-3+5-7+...+17

=(1-3)+(5-7)+(9-11)+(13+15)+17

=(-2)+(-2)+(-2)+(-2)+17

=(-8)+17

=9

S1=9

S2=-2+4+(-6)+8+...+(-18)

 =[(-2)+4]+[(-6)+8]+[(-10)+12]+[(-14)+16]+(-18)

=2+2+2+2+(-18)

=8+(-18)

= -10

S2=-10

S1+S2=9+(-10)= -1

\(\frac{2003\times4+1998+2001\times2002}{2002+2002\times1002+2002\times1003}\)

\(=\frac{2003\times4+2\times999+2001\times2\times1001}{2002.\left(1+1002+1003\right)}\)

\(=\frac{2\times\left(2003\times2+999+2001\times1001\right)}{1001\times2\times\left(1+1002+1003\right)}\)

\(=\frac{2003\times2+999+2001\times1001}{1001\times\left(1+1002+1003\right)}\)

\(=1\)

mk ko bít

1) \(\left(+15\right)+\left(+17\right)=15+17=32\)

2) \(\left(-3\right)+\left(-7\right)=-3-7=-\left(3+7\right)=-10\)

3) \(\left(-25\right)+\left(+4\right)=-25+4=-\left(25-4\right)=-21\)

4) \(\left(-6\right)+\left(-54\right)=-6-54=-\left(6+54\right)=-60\)

5) \(\left(-15\right)+20=20-15=5\)

6) \(\left(-5\right)+8+7+5\)

\(=\left(-5+5\right)+\left(8+7\right)\)

\(=15\)

7) \(\left(-8\right)+\left(-11\right)+\left(-2\right)\)

\(=\left[\left(-8\right)+\left(-2\right)\right]+\left(-11\right)\)

\(=\left(-10\right)+\left(-11\right)\)

\(=-21\)

8) \(15+\left(-5\right)+\left(-14\right)+\left(-16\right)\)

\(=\left[15+\left(-5\right)\right]+\left[\left(-14\right)+\left(-16\right)\right]\)

\(=10+\left(-30\right)\)

\(=-20\)

9) \(\left(-20\right)+\left(-14\right)+3+\left(-86\right)\)

\(=\left[\left(-20\right)+3\right]+\left[\left(-14\right)+\left(-86\right)\right]\)

\(=\left(-17\right)+\left(-100\right)\)

\(=-117\)

10) \(\left(-136\right)+123+\left(-264\right)+\left(-83\right)+240\)

\(=\left[\left(-136\right)+\left(-264\right)\right]+\left[123+\left(-83\right)\right]+240\)

\(=\left(-400\right)+40+240\)

\(=\left(-360\right)+240\)

\(=-120\)

11) \(\left(-596\right)+2001+1999+\left(-404+189\right)\)

\(=\left(-596\right)+2001+1999-404+189\)

\(=\left[\left(-596\right)-404\right]+\left(2001+189\right)+1999\)

\(=\left(-1000\right)+2190+1999\)

\(=1190+1999\)

\(=3189\)

12) \(314+\left(-153\right)+64+121+\left(-247\right)+218\)

\(=\left(314+64+121\right)+\left[\left(-153\right)+\left(-247\right)\right]+218\)

\(=\left(378+121\right)+\left(-400\right)+218\)

\(=499-400+218\)

\(=99+218\)

\(=317\)

\(\text{#}Toru\)