23-(-27)+(-50) = 0
234+(-117)-100+(-234) = -217
-927-(-1421)-(930)+(-1421) = -1020
2021-[-2022-(-2021)] = 2021
1-2+3-4+...+2021-2022=
A=1-2+3-4+...+2021-2022
=(1-2)+(3-4)+...+(2021-2022) (có tất cả 1011 cặp)
=(-1).(-1)...(-1)
=(-1).1011=-1011
HOk tốt!!!!!!!!!!!!!
23 - ( - 27 ) + ( - 50 ) = 0
234 + ( - 117 ) - 100 + ( - 234 ) = - 217
- 927 - ( - 1421 ) - ( 930 ) + ( - 1421 ) = 985
2021 - [ - 2022 - ( - 2021 )] = 2022
1 - 2 + 3 - 4 + ...+ 2021 - 2022
=(1-2)+(3-4)+...+(2021-2022)
=(-1)+(-1)+...
=(-1)x(2022:2)
= -1011
\(a)23-\left(-27\right)+\left(-50\right).\)
\(=23+27-50\)
\(=50-50=0\)
\(b)234+\left(-117\right)-100+\left(-234\right)\)
\(=\left[234+\left(-234\right)\right]+\left[\left(-117\right)-100\right]\)
\(=0+\left(-217\right)\)
\(=-217\)
\(c)-927-\left(-1421\right)-\left(-930\right)+\left(-1421\right)\)
\(=-927+1421+930-1421\)
\(=\left(-927+930\right)+\left(1421-1421\right)\)
\(=3+0=3\)
\(d)2021-\left[-2022-\left(-2021\right)\right]\)
\(=2021-\left(-2022+2021\right)\)
\(=2022\)
\(e)1-2+3-4+...+2021-2022\)
\(=\left(1-2\right)+\left(3-4\right)+...+\left(2021-2022\right)\)
\(=-1+\left(-1\right)+...+\left(-1\right)\)
\(=-1\times1011\)
\(=-1011\)
\(#Wee\)
dạ cảm ơn các bạn đã quan tâm bài của mink nhưng mink cần lời giải cụ thể được không ạk?
a ) 23-(-27)+(-50) =
= 23 + 27 - 50
= 50 - 50
= 0
b ) 234+(-117)-100+(-234) =
= 234 - 117 - 100 - 234
= ( 234 - 234 ) + ( - 117 - 100 )
= 0 + (- 217 )
= -217
c ) -927-(-1421)-(930)+(-1421) =
= - 927 + 1421 - 930 - 1421
= ( 1421 - 1421 ) + ( -927 - 930 )
= 0 + ( -1857 )
= -1857
d ) 2021-[-2022-(-2021)] =
= 2021 - ( -2022 + 2021 )
= 2021 - ( - 1 )
= 2021 + 1
= 2022
HOk tốt!!!!!!!!!
1-2+3-4+...+2021-2022 =
=1-2+3-4+...+2021-2022
=(1-2)+(3-4)+...+(2021-2022) (có tất cả 1011 cặp)
=(-1).(-1)...(-1)
=(-1).1011=-1011
Hok tốt!!!!!!!!!!!!
