= mười ko ha ngoc chi

 mình trả lời mấy lần nhưng toàn hiên ra = 1 thôi à

= 1 ko ha ngoc chi

= 1 ko ha ngoc chi

5/6 x 1/7 - 1/7 x 1/6

= 1/7 x (5/6 - 1/6)

= 1/7 x 2/3

= 2/21

8/15 : 4/5 x 3/2

= 2/3 x 3/2

= 1

a: =1/7(5/6-1/6)=1/7x2/3=2/21

b: =8/15x5/4x3/2=1

`5/6xx1/7-1/7xx1/6`

`= 1/7 xx (5/6-1/6)`

`= 1/7 xx 2/3`

`= 2/21`

`8/15: 4/5 xx3/2`

`= 2/3 xx 3/2`

`= 1`

 5 + (-12)-10 = (-7) - 10 = -17

   \(5 + (-12) - 10\)

\(= 5 - 12 - 10\)

\(= (-7) - 10\)

\(= -17\)

-2 nhé em yêu

\(a,\frac{21}{11}\cdot\frac{22}{17}\cdot\frac{68}{63}=\frac{21\cdot22\cdot68}{11\cdot17\cdot63}=\frac{21\cdot11\cdot2\cdot17\cdot4}{11\cdot17\cdot21\cdot3}=\frac{8}{3}\)

\(b,\frac{5}{14}\cdot\frac{7}{13}\cdot\frac{26}{25}=\frac{5\cdot7\cdot26}{14\cdot13\cdot25}=\frac{5\cdot7\cdot13\cdot2}{7\cdot2\cdot13\cdot5\cdot5}=\frac{1}{5}\)

a)  \(\frac{21}{11}\times\frac{22}{17}\times\frac{68}{63}=\frac{21\times22\times68}{11\times17\times63}\)

\(=\frac{21\times2\times11\times4\times17}{11\times17\times3\times21}\)

\(=\frac{8}{3}\)

b)  \(\frac{5}{14}\times\frac{7}{13}\times\frac{26}{25}=\frac{5\times7\times26}{14\times13\times25}\)

\(=\frac{5\times7\times2\times13}{2\times7\times13\times5\times5}\)

\(=\frac{1}{5}\)

dấu chấm là gì vậy bạn cô gái

 cô đơn

Bài 1 :

Gọi \(A=5+5^2+5^3+...+5^{98}+5^{99}\\ 5A=5^2+5^3+5^4+...+5^{99}+5^{100}\\ 5A-A=\left(5^2+5^3+5^4+...+5^{99}+5^{100}\right)-\left(5+5^2+5^3+...+5^{98}+5^{99}\right)\\ 4A=5^{100}-5\\ A=\dfrac{5^{100}-5}{4}\)

Bài 2:

\(\left(12x-4\right)\cdot8^{2022}=4\cdot8^{2023}\\ 12x-4=4\cdot8^{2023}:8^{2022}\\ 12x-4=4\cdot8\\ 12x-4=32\\ 12x=36\\ x=3\)

16.9454545455

\(=\left(1,1+1,9\right)+\left(1,2+1,8\right)+\left(1,3+1,7\right)+\left(1,4+1,6\right)+1,5\)
\(=3+3+3+3+1,5\)
\(=13,5\)

1,1 + 1,2 + 1,3 + 1,4 + 1,5 + 1,6 + 1,7 + 1,8 + 1,9

= ( 1,1 + 1,9 ) + ( 1,2 + 1,8 ) + ( 1,3 + 1,7 ) + ( 1,4 + 1,6 ) + 1,5

=     3 + 3 + 3 + 3 + 1,5

= 3 \(\times\) 4 + 1,5 

= 12 + 1,5

= 13,5

7 + 7 : 7 + 7 x 7 - 7

= 7 + 1 + 49 - 7

= (7 - 7) + (1 + 49)

= 0 + 50

= 50

k cho tớ nha

50 k nhé

=7+1+49-7

=(7-7)+(49+1)

=0+50=50

E= 2925

F= 951 

nho k cho minh nha minh dang can diem

mk cần cả bài

E= 1x1+3x3+5x5+7x7+9x9+11x11+13x13+15x15+17x17+19x19+21x21+25x25=2925

F= 4x4+7x7+10x10+13x13+16x16+19x19=951

bai nhu vay day cho minh xin mot k nha ko co cung duoc

Bài 1: Tính
a, 1/2 x 2/3 x 3/4 = 1/4
b, 7/8 x 8/9 x 9/10 = 7/10
c, 5/14 x 7/15 x 28/7 = 2/3
d, 2 x 1/2 x 3 x 1/3 x 4 x 1/4 x 5 x 1/5 = 1
Bài 2: Tính
a, 7/20 - ( 5/8 - 3/5 ) = 7/20 - 1/40 = 14/40 - 1/40 = 13/40
b, 5/6 + ( 5/9 - 1/4 ) = 5/6 + 11/36 = 30/36 + 11/36 = 41/36
c, 9/10 - ( 2/5 + 3/10 ) + 7/20 = 9/10 - 7/10 + 7/20 = 2/10 + 7/20 = 4/20 + 7/20 = 11/20.
Bài 3: Tìm x:
a, 1/2 + x = 5/6
x = 5/6 - 1/2
x = 1/3
b, 5/6 - x = 1/3
x = 5/6 - 1/3
x = 1/2
c, x - 1/mấy vậy bạn
d, 1/3 x x = 1/6
x = 1/6 : 1/3
x = 1/2