\(11=\frac{77}{7}< \frac{78}{7}\Rightarrow-\frac{11}{3^7\cdot7^3}>-\frac{78}{3^7\cdot7^4}\)

\(\frac{-11}{3^7.7^3}>\frac{-78}{3^7.7^4}\)

bạn có thể ghi rõ ko

7 . 7 

= 49

đ/s : 49

7.7

= 49

7.7 = 49 

nho ket ban voi minh voi

có - 11/3^7.7^3 =-77/3^7.7^4 rồi so sánh với -78/3^7.7^4 nhé :))

ai cứu với ạ

1.2+2.9+3.7+7.7=2.(1+9)+7.(3+7)

                          =2.10+7.10

                          =(2+7).10

                          =9.10

                          =90

1.2+2.9+3.7+7.7

=2+18+21+49

=20+21+49

=41+49

=90

=49

=6

k nha bn

7.7=49

2.3=6

7.7=49

2.3=6

`4 . 5/7`

`=20/7`

__

`22/23 . 9/11`

`= 22.9/23.11`

`= 2.9/23.1`

`= 18/23`

__

`-9/7 . 7/15`

`= -9/15`

`= - 3/5`

\(a,4.\dfrac{5}{7}=\dfrac{4.5}{7}=\dfrac{20}{7}\)

\(b,\dfrac{22}{23}.\dfrac{9}{11}=\dfrac{22.9}{23.11}=\dfrac{198}{253}=\dfrac{18}{23}\)

\(c,\dfrac{-9}{7}.\dfrac{7}{15}=\dfrac{-9.7}{7.15}=\dfrac{-63}{105}=\dfrac{-3}{5}\)

`3/7 .4/11+3/7 .7/11-2`

`= 3/7 . ( 4/11 + 7/11)-2`

`= 3/7 . 11/11 -2`

`=3/7 . 1-2`

`= 3/7-2`

`= 3/7 - 14/7`

`=-11/7`

`3/7*4/11+3/7*7/11-2`

`=3/7*(4/11+7/11)-2`

`=3/7*1-2`

`=3/7-2`

`=3/7-14/7`

`=-11/7`

= -11/7