\(A=\frac{3^{10}+1}{3^9+1}=\frac{3^{10}+3-2}{3^9+1}=\frac{3\left(3^9+1\right)-2}{3^9+1}=3-\frac{2}{3^9+1}\)

\(B=\frac{3^9+1}{3^8+1}=\frac{3^9+3-2}{3^8+1}=\frac{3\left(3^8+1\right)-2}{3^8+1}=3-\frac{2}{3^8+1}\)

Có \(3^9+1>3^8+1\)

\(\Rightarrow\frac{2}{3^9+1}< \frac{2}{3^8+1}\)

\(\Rightarrow3-\frac{2}{3^9+1}>3-\frac{2}{3^8+1}\)

\(\Rightarrow A>B\)

biết................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. chết liền

Living on Mars sounds very exciting to me

gọi d là ƯC(7n + 4; 5n + 3) 

=> 7n + 4 và 5n + 3 ⋮ d

=> 5(7n + 4) và 7(5n + 3) ⋮ d

=> 35n + 20 và 35n + 21 ⋮ d

=> (35n + 21) - (35n +20) ⋮ d

=> 1 ⋮ d

=> d = + 1

=> 7n+4/5n+3 là phân số tối giản

Gọi a C Ư(7n+4;5n+3)

=>7n+4 và 5n+3 đều chia hết cho a

=>5(7n+4) và 7(5n+3) chia hết cho a

=>35n+20 và 35n+21 chia hết cho a

=>(35n+21) - (35n+20) chia hết cho a

=>1chia hết cho a

=>d C { + 1 }
Vậy7n+45n+3 là phân số tối giản

im lặng là vàng

thời gian à

Mỗi người cần phải

Ko được đụng vào các chỗ ...{bộ phận của người khác} kể cả gái hay tra

\(A=\frac{100^{2017}+1}{100^{2018}+1}\)

\(\Rightarrow100A=\frac{100\cdot\left[100^{2017}+1\right]}{100^{2018}+1}\)

\(\Rightarrow100A=\frac{100^{2018}+100}{100^{2018}+1}\)

\(\Rightarrow100A=\frac{100^{2018}+1+99}{100^{2018}+1}\)

\(\Rightarrow100A=1+\frac{99}{100^{2018}+1}\)

\(B=\frac{100^{2018}+1}{100^{2019}+1}\)

\(\Rightarrow100B=\frac{100\cdot\left[100^{2018}+1\right]}{100^{2019}+1}\)

\(\Rightarrow100B=\frac{100^{2019}+100}{100^{2019}+1}\)

\(\Rightarrow100B=\frac{100^{2019}+1+99}{100^{2019}+1}\)

\(\Rightarrow100B=1+\frac{99}{100^{2019}+1}\)

Tự so sánh

\(A=\frac{100^{2017}+1}{100^{2018}+1}\)

\(\Rightarrow100A=\frac{100^{2018}+100}{100^{2018}+1}\)

\(\Rightarrow100A=\frac{100^{2018}+1+99}{100^{2018}+1}\)

\(\Rightarrow100A=\frac{100^{2018}+1}{100^{2018}+1}+\frac{99}{100^{2018}+1}\)

\(\Rightarrow100A=1+\frac{99}{100^{2018}+1}\)(1)

\(B=\frac{100^{2018}+1}{100^{2019}+1}\)

\(\Rightarrow100B=\frac{100^{2019}+100}{100^{2019}+1}\)

\(\Rightarrow100B=\frac{100^{2019}+1+99}{100^{2019}+1}\)

\(\Rightarrow100B=\frac{100^{2019}+1}{100^{2019}+1}+\frac{99}{100^{2019}+1}\)

\(\Rightarrow100B=1+\frac{99}{100^{2019}+1}\)(2)

Từ (1) và (2) suy ra 100A > 100B hay A > B

Do as directed

1.  / / / // / // ( Rearrange these worlds in order)

->.....................My future house will be surrounded by tall trees and blue sea.............................

2. We tried our best, but we didn't win the game. ( Use Although)

-> Although..................We tried our best,  we didn't win the game.....................

3. No mountain in Viet Nam is higher than Phanxipang. ( Use the Superlative of Adjective)

-> Phanxipang...........is the highest in VN...........................................

4. He goes to an English speaking club twice a week ( Make the question for underlined worlds)

->...........How often does he go to an English speaking club?......................................

5. We pollute the air. We have breathing problems. ( Use conditional sentence)

->.....................IF We didn't pollute the air,we wouldn't have breathing problems. ..............

6. Hung is putting his feet on the bench

-> You say:'' Don't..........put your feet on the beach,Hung.........................''

phân số chỉ số trang sách Mai đọc cả ngày thứ 2 & 3 là :

\(1-\frac{1}{4}=\frac{3}{4}\left(trang\right)\)

đổi :\(55\%=\frac{11}{20}\)

số trang sách đọc dc ngày thứ 2 chiếm :

\(\frac{3}{4}\cdot\frac{11}{20}=\frac{33}{80}\left(trang\right)\)

phân số chỉ ngày thứ 3 đọc dc là :

\(1-\frac{1}{4}-\frac{33}{80}=\frac{27}{80}\left(trang\right)\)

Cuốn sách có số trang là :

\(54:\frac{27}{80}=160\left(trang\right)\)

Đáp số : 160 trang 

gọi d là ƯC(7n + 4; 5n + 3) 

=> 7n + 4 và 5n + 3 ⋮ d

=> 5(7n + 4) và 7(5n + 3) ⋮ d

=> 35n + 20 và 35n + 21 ⋮ d

=> (35n + 21) - (35n +20) ⋮ d

=> 1 ⋮ d

=> d = + 1

=> 7n+4/5n+3 là phân số tối giản

Đặt \(\left(7n+4;5n+3\right)=d\)

\(\Rightarrow\hept{\begin{cases}7n+4⋮d\\5n+3⋮d\end{cases}\Rightarrow\hept{\begin{cases}5.\left(7n+4\right)⋮d\\7.\left(5n+3\right)⋮d\end{cases}}}\)

                                \(\Rightarrow\hept{\begin{cases}35n+20⋮d\\35n+21⋮d\end{cases}}\)

\(\Rightarrow\left(35n+21\right)-\left(35n+20\right)⋮d\)

\(\Rightarrow1⋮d\)

\(\Rightarrow d\inƯ\left(1\right)=\left\{\pm1\right\}\)

\(\Rightarrow\frac{7n+4}{5n+3}\)là phân số tối giản 

mình làm tắt nha

có số hs TB là

\(48.\frac{5}{12}=20\)(bạn)

có số hs giỏi là:

\(48-\orbr{ }\left(48-20\right).\frac{4}{7}+20\)=12 bạn

đáp số 12 bạn