`a)25/(x+1)-1 1/6=-1/3-0,5`

`=>25/(x+1)=-1/3-1/2+1+1/6`

`=>25/(x+1)=1/3`

`=>75=x+1`

`=>x=74`

Vậy `x=74`

`b)(2x+25 3/5)^2-9/25=0`

`=>(2x+128/5)=9/25`

`**2x+128/5=3/5`

`=>2x=-125/5=-25`

`=>x=-25/2`

`**2x+128/5=-3/5`

`=>2x=-131/5`

`=>x=-131/10`

Giải:

a) \(\dfrac{25}{x+1}-1\dfrac{1}{6}=\dfrac{-1}{3}-0,5\) 

              \(\dfrac{25}{x+1}=\dfrac{-5}{6}+\dfrac{7}{6}\) 

              \(\dfrac{25}{x+1}=\dfrac{1}{3}\) 

\(\Rightarrow1.\left(x+1\right)=25.3\)  

\(\Rightarrow x+1=75\) 

\(\Rightarrow x=75-1\) 

\(\Rightarrow x=74\) 

b) \(\left(2x+25\dfrac{3}{5}\right)^2-\dfrac{9}{25}=0\) 

              \(\left(2x+\dfrac{128}{5}\right)^2=0+\dfrac{9}{25}\) 

             \(\left(2x+\dfrac{128}{5}\right)^2=\dfrac{9}{25}\) 

\(\Rightarrow\left[{}\begin{matrix}\left(2x+\dfrac{128}{5}\right)^2=\left(\dfrac{3}{5}\right)^2\\\left(2x+\dfrac{128}{5}\right)^2=\left(\dfrac{-3}{5}\right)^2\end{matrix}\right.\) 

\(\Rightarrow\left[{}\begin{matrix}2x+\dfrac{128}{5}=\dfrac{3}{5}\\2x+\dfrac{128}{5}=\dfrac{-3}{5}\end{matrix}\right.\) 

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{-25}{2}\\x=\dfrac{-131}{10}\end{matrix}\right.\) 

Chúc bạn học tốt!

= ( 2380 + 9 x 480) : 25 - 3500 : 25 

= ( 2380 + 4320 - 3500 ) : 25 

= 3200 : 25 

= 128

Gọi tổng của phép tính trên là A

\(A=15+2^4+2^5+2^6+...+2^{2022}\)

\(\Rightarrow2A=2+2^2+...+2^{2023}\)

\(\Rightarrow A=2^{2023}-1\)

KHO THE

\(A=\frac{\left[\left(25-1\right):1+1\right]\left(25+1\right)}{2}=325.\)

\(B=\frac{\left[\left(51-3\right):2+1\right]\left(51+3\right)}{2}=675\)

\(C=\frac{\left[\left(81-1\right):4+1\right]\left(81+1\right)}{2}=861\)

Kết quả bằng 8,08 !

chỉ mình cách làm với,được không bạn

a: \(-145\cdot\left(13-57\right)+57\left(10-145\right)\)

\(=-145\cdot13+145\cdot57+57\cdot10-57\cdot145\)

\(=-145\cdot13+57\cdot10\)

=-1885+570

=-1315

b: \(17\left(15-16\right)+16\left(17-20\right)\)

\(=17\cdot15-17\cdot16+16\cdot17-16\cdot20\)

\(=17\cdot15-16\cdot20=255-320=-65\)

c: \(-38\left(25-4\right)+25\left(-4+38\right)\)

\(=-38\cdot25+38\cdot4-25\cdot4+25\cdot38\)

\(=38\cdot4-25\cdot4=4\cdot13=52\)

[-1/7]=-1

[3,7]=3

[-4]=-4

[-43/10]=[-4,3]=-5