K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

DT
12 tháng 4

\(\dfrac{1\times3\times5\times39}{3\times19\times5\times3\times3}=\dfrac{39}{57}\)

28 tháng 10 2016

\(45\times1+45\times2+45\times3+45\times4+45\times5+45\times15+45\times20+45\times50\)

\(=45\times\left(1+2+3+4+5+15+20+50\right)\)

\(=45\times100\)

\(=4500\)

17 tháng 12 2016

kết quả bằng : 4500 chac chan minh tinh bang may tinh ma 

chúc bạn học giỏi 

2 tháng 1

    -5 + (-37 - 45 + 51) - (-37 + 51)

=  -5  - 37 - 45 + 51 + 37 - 51

=  - (5 + 45) - (37 - 37) + (51 - 51)

= - 50 - 0 + 0

= - 50

  - (15 - 47 + 58) + (15 - 47 ) + 3

= - 15 + 47 - 58 + 15 - 47 + 3

= (-15 + 15) + (47 - 47) - (58 - 3)

= 0 + 0 - 55

= - 55

 

2 tháng 1

  (53 - 45 - 49) - (53 + 45 - 49)

= 53 -  45 - 49 - 53 - 45 + 49

= (53 - 53) + (-49 + 49) - (45 + 45)

= 0 + 0 - 90

= - 90 

    13 - 15 + 49 - 13 + 15 - 48

=  (13 - 13) + (-15 + 15) + (49 - 48)

= 0 + 0 + 1

=  1 

a: =4(3h15'+2h4')=4(195'+124')=1276'

b: =3(15'45s-6'45s)=3x9'=27'

1 tháng 12 2021

-5 + ( -37 - 45 + 51 ) - ( -37 + 51 ) 

=-5+ -37 - 45 + 51- -37 + 51 

=(37+(-37) +(51-(-51) + (45 - (-5)

=0+0+50

=50

MIK MỚI LÀM ĐC PHẦN A)

5 tháng 12 2021

\(1,=38-42+14-25+27+15=27\)

\(2,=12+21-23+21-10=21\)

\(3,=57-725-605+53=-1220\)

\(4,=55+45+15-15+55-45=110\)

5 tháng 12 2021

\(\text{1.(38-42+14)-(25-27-15)}\\ =38-42+14-25+27+15\\ =-4-11+42\\ =27\)

\(\text{2.(12+21)-(23-21+10)}\\ =12+21-23+21-10\\ =33+44-10=67\)

1.

\(\left(572\cdot7+266\right)\cdot\left(366\cdot9-168\cdot18\right)\cdot\left(346\cdot6-348\right)\)

\(=\left(286\cdot7\cdot2+133\cdot2\right)\cdot\left(366\cdot9-168\cdot2\cdot9\right)\cdot\left(173\cdot6\cdot2-174\cdot2\right)\)

\(=\left(2002\cdot2+133\cdot2\right)\cdot\left(366\cdot9-336\cdot9\right)\cdot\left(1038\cdot2-174\cdot2\right)\)

\(=\left[2\cdot\left(2002+133\right)\right]\cdot\left[9\cdot\left(366-336\right)\right]\cdot\left[2\cdot\left(1038-174\right)\right]\)

\(=2\cdot2135\cdot9\cdot30\cdot2\cdot864\)

\(=4270\cdot9\cdot30\cdot2\cdot864\)

\(=\left(4270\cdot30\right)\cdot9\cdot2\cdot864\)

\(=\left(427\cdot10\right)\cdot\left(3\cdot10\right)\cdot9\cdot2\cdot864\)

\(=\left(427\cdot3\right)\cdot\left(10\cdot10\right)\cdot9\cdot2\cdot864\)

\(=1281\cdot100\cdot9\cdot2\cdot864\)

\(=\left(1281\cdot100\right)\cdot\left(9\cdot2\cdot864\right)\)

\(=\left(1281\cdot100\right)\cdot15552\)

\(=\left(1281\cdot15552\right)\cdot100\)

\(=19922112\cdot100\)

\(=1992211200\)

2.

\(\left(1+3+5+7+...+97+9\right)\cdot\left(45\cdot3-15\cdot2-45\right)\)

\(=\left(1+3+5+7+...+97+9\right)\cdot\left(15\cdot3\cdot3-15\cdot2-15\cdot3\right)\)

\(=\left(1+3+5+7+...+97+9\right)\cdot\left[15\cdot\left(3\cdot3\right)-15\cdot2-15\cdot3\right]\)

\(=\left(1+3+5+7+...+97+9\right)\cdot\left(15\cdot9-15\cdot2-15\cdot3\right)\)

\(=\left(1+3+5+7+...+97+9\right)\cdot\left[15\cdot\left(9-2-3\right)\right]\)

\(=\left(1+3+5+7+...+97+9\right)\cdot15\cdot4\)

\(=\left[\left(1+3+5+7+...+97\right)+9\right]\cdot\left(15\cdot4\right)\)

Trong \(\left(1+3+5+7+...+97\right)\) có số số hạng là:

        \(\left(97-1\right)\div2+1=49\) ( số hạng )

\(\Rightarrow\left[\left(1+3+5+7+...+97\right)+9\right]\cdot\left(15\cdot4\right)\)

\(=\left[\left(97+1\right)\cdot49\div2\right]\cdot\left(15\cdot4\right)\)

\(=2401\cdot60\)

\(=\left(2401\cdot6\right)\cdot10\)

\(=14406\cdot10\)

\(=144060\)

3.

\(\left(180\div15-132\div11\right)\cdot\left(57869-297\div11\cdot108\right)\)

\(=\left(12-12\right)\cdot\left(57869-297\div11\cdot108\right)\)

\(=0\cdot\left(57869-297\div11\cdot108\right)\)

\(=0\)

Sửa lại bài 2; dòng 11 ( từ đề bài bài 2 ):

\(=\left\{\left[\left(97+1\right)\cdot49\div2\right]+9\right\}\cdot\left(15\cdot4\right)\)

\(=\left(2401+9\right)\cdot\left(15\cdot4\right)\)
\(=2410\cdot\left(15\cdot4\right)\)

\(=2410\cdot60\)

\(=\left(241\cdot10\right)\cdot\left(6\cdot10\right)\)

\(=\left(241\cdot6\right)\cdot\left(10\cdot10\right)\)

\(=1446\cdot10\)

\(=14460\)

6 tháng 12 2021

1) -1

2) -1326

3) 90

14 tháng 5 2021

E nha 

\(\dfrac{15^{30}}{45^{15}}=\dfrac{5^{15}.3^{15}.15^{15}}{3^{15}.15^{15}}=5^{15}\)

14 tháng 5 2021

\(\dfrac{15^{30}}{45^{15}}=\dfrac{15^{2\cdot15}}{45^{15}}=\dfrac{\left(15^2\right)^{15}}{45^{15}}=\dfrac{225^{15}}{45^{15}}=\left(\dfrac{225}{45}\right)^{15}=5^{15}\)

30 tháng 9 2023

\(\dfrac{45}{15}-\left\{\dfrac{1}{2}+\left[\dfrac{1}{3}+\left(\dfrac{1}{4}\right)^{-1}\right]^{-1}\right\}^{-1}\)

\(=3-\left[\dfrac{1}{2}+\left(\dfrac{1}{3}+4\right)^{-1}\right]^{-1}\\ =3-\left(\dfrac{1}{2}+\dfrac{3}{13}\right)^{-1}\\ =3-\left(\dfrac{19}{26}\right)^{-1}\\ =3-\dfrac{26}{19}\\ =\dfrac{31}{19}\)

Bạn xem lại bài.

3 tháng 3 2023

`4/7+4`

`=4/7+4/1`

`=4/7+28/7`

`=32/7`

__

`3+6/11`

`=33/11+6/11`

`=39/11`

__

`3-5/7`

`=3/1-5/7`

`=21/7-5/7`

`=16/7`

__

`21/9-2`

`=21/9-18/9`

`=3/9`

`=1/3`

__

`15/24+2`

`=15/24+48/24`

`=63/24`

`=21/16`

__

`63/45-20/25`

`=63/45-4/5`

`=63/45-36/45`

`=27/45`

`=9/15`

__

`3/4-2/8`

`=3/4-1/4`

`=2/4`

__

`6/7-5/8`

`=48/56-35/56`

`=13/56`

__

`37/45-5/9`

`=37/45-25/45`

`=12/45`

`=4/15`

__

`46/39-11/13`

`=46/39-33/39`

`=13/39`

`=1/2`

__

`5/12+3/4+1/3`

`=5/12+9/12+4/12`

`=14/12+4/12`

`=18/12`

`=3/2`

__

`1/2+3/7+11/14`

`=7/14+6/14+11/14`

`=13/14+11/14`

`=24/14`

`=12/7`

__

`7/10-(1/5+1/4)`

`=7/10-(4/20+5/20)`

`=7/10-9/20`

`=14/20-9/20`

`=5/20`

`=1/4`

__

`15/4-2/3-3/4`

`=(15/4-3/4)-2/3`

`=12/4-2/3`

`=3-2/3`

`=9/3-2/3`

`=7/3`