a) \(\left(-48\right)+10+\left(-22\right)+\left(-10\right)\)

\(=\left[\left(-48\right)+\left(-22\right)\right]+\left(-10+10\right)\)

\(=-70+0=-70\)

Tham khảo <3

= -70 

( hihi )

(-48)+(-22)+(10-10)

=-70 +0

=-70

a) \(153^2-53^2=\left(153-53\right)\left(153+53\right)=100.206=20600\)

b)

\(\left(2020^2-2019^2\right)+\left(2018^2-2017^2\right)+...+\left(2^2-1^2\right)\\ =\left(2020+2019\right)\left(2020-2019\right)+\left(2018+2017\right)\left(2018-2017\right)+...+\left(2+1\right)\left(2-1\right)\\ =2020+2019+2018+2017+...+2+1\\ =\dfrac{\left(2020+1\right)2020}{2}=2041210\)

Lời giải:

a. $153^2-53^2=(153-53)(153+53)=100.206=20600$

b. 

$2020^2-2019^2+2018^2-2017^2+...+2^2-1^2$

$=(2020^2-2019^2)+(2018^2-2017^2)+...+(2^2-1^2)$

$=(2020-2019)(2020+2019)+(2018-2017)(2018+2017)+...+(2-1)(2+1)$

$=2020+2019+2018+2017+...+2+1$

$=\frac{2020.2021}{2}=2041210$

a) 153²-53²=(153-53)(153+53)=100.206=20600

`b)48/100+22/100+5/100+25/100`

`=>(48/100+22/100)+(5/100+25/100)`

`=>70/100+70/100`

`=>100/100=1`

a,3,31x5+6x3,31-3,31                       

=3,31x(5+6-1)

=3,31x10

=33,1

b) 48/100+22%+5/100+0,25

=48%+22%+5%+25%

=1

a,3,31x5+6x3,31-3,31       

=3,31x5+6x3,31-3,31x1

=3,31 x ( 5+6-1)

= 3,31 x10

= 33,1

 b,48/100+22%+5/100+0,25

= 0,48 +0,22 + 0,05 +0,25

=    1

\(a,12.\dfrac{-7}{11}.\dfrac{5}{6}.\dfrac{22}{7}=\left(12.\dfrac{5}{6}\right)\left(\dfrac{-7}{11}.\dfrac{22}{7}\right)=10.\left(-2\right)=-20\\ b,\dfrac{-8}{15}.\dfrac{7}{9}.\dfrac{5}{8}.\left(-18\right)=\left(\dfrac{-8}{15}.\dfrac{5}{8}\right)\left[\dfrac{7}{9}.\left(-18\right)\right]=\dfrac{-1}{3}.\left(-14\right)=\dfrac{14}{3}\)

a) 12.−711.56.227= (12.56)(−711.227)= 10.(−2)= −20.

b) −815.79.58.(−18)= (−815.58)[79.(−18)]= −13.(−14)= 143.

2. 314 cm²

3. số các số là: (2022-2):10+1 = 203 số

2x12x22x32x42x..........x2002x2012x2022 = (2x12x22x32)....(1962x1972x1982x1992)x(2002x2012x2022)

= (...6)....(...6)x(...8)

= ... 8

vậy chữ số tận cùng là 8

duyệt đi

2 : 314 cm²

^{3: 192}

^{4 : 945}

^{5 : 375}

4. ab,c=a,bcx10

a,bc+1-xa,bc=21,12

a,bcx11=21,12

a,bc=1,92

abc=192

bằng 88

>> Trả lời:

22 + 22 + 22 + 22 => 22 x 4 => 88.

#moonpink#

bằng 88 nhé bn

Nguyễn Quang Thành trả lời cụ thể đi

.....=19 nha bn