a. \(\frac{x+1}{2}=\frac{8}{x+1}\)
\(\Leftrightarrow\left(x+1\right).\left(x+1\right)=8.2\)
\(\Leftrightarrow\left(x+1\right)^2=16\)
\(\Leftrightarrow\left(x+1\right)^2=2^4\)
\(\Leftrightarrow\left(x+1\right)=2^2\)
\(\Leftrightarrow\left(x+1\right)=4\)
\(\Leftrightarrow x=4-1=3\)
b. \(x:\left(9\frac{1}{2}-\frac{3}{2}\right)=\frac{0,4+\frac{2}{9}-\frac{2}{11}}{1,6+\frac{8}{9}-\frac{8}{11}}\)
\(\Leftrightarrow x:\left(\frac{10}{2}-\frac{3}{2}\right)=\frac{0,4+0,2-0,18}{1,6+0,8-0,72}\)
\(\Leftrightarrow x:\frac{7}{2}=\frac{\frac{21}{50}}{\frac{42}{25}}\)
\(\Leftrightarrow x=\frac{\frac{21}{50}}{\frac{42}{25}}.\frac{7}{2}\Leftrightarrow x=\frac{1}{4}.\frac{7}{2}=\frac{7}{8}\)
a ) \(\frac{x+1}{2}=\frac{8}{x+1}\)
\(\Rightarrow\left(x+1\right).\left(x+1\right)=2.8\)
\(\Rightarrow\left(x+1\right)^2=16\)
\(\Rightarrow\orbr{\begin{cases}x+1=4\\x+1=-4\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=4-1\\x=-4-1\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=3\\x=-5\end{cases}}\)
Dấu " \(\orbr{\begin{cases}\\\end{cases}}\)là hoặc nha !!!
a)\(\frac{x+1}{2}=\frac{8}{x+1}\)
\(\Rightarrow\left(x+1\right)^2=8\times2=16\)
\(\Rightarrow\left(x+1\right)^2=4^2\)
\(\Rightarrow x+1=4\)
\(\Rightarrow x=4-1=3\)
b)tớ ko biết làm . ~ sorry~
~chuk bn hok giỏi~
câu a mk thiếu \(\orbr{\begin{cases}\left(x+1\right)^2\\\left(x+1\right)^2=4^2\end{cases}}=\left(-4\right)^2\)
a) x+1/2=8/x+1
Suy ra (x+1)(x+1)=2.8
Suy ra (x+1)^2=16
Suy ra (x+1)^2=4^2
Suy ra x+1=4 Suy ra x=3
b) x : (9 1/2-3/2) = 0.4 + 2/9 - 2/11 / 1.6 + 8/9 - 8/11
x: 8= 2/5 + 2/9 - 2/11 / 8/5 + 8/9 + 8/11
x:8= 2 (1/5 + 1/9 - 1/11) / 8 ( 1/5 + 1/9 - 1/11)
x:8=1/4
x=2
a)\(\left(x+1\right).\left(x+1\right)=8.2\)
\(\left(x+1\right)^2=16\)
\(\left(x+1\right)^2=4^2\)
\(x+1=4\)
\(x=4-1\)
\(x=3\)
Ta có :
\(\frac{x+1}{2}=\frac{8}{x+1}\)
\(\Leftrightarrow\)\(\left(x+1\right)\left(x+1\right)=2.8\)
\(\Leftrightarrow\)\(\left(x+1\right)^2=16\)
\(\Leftrightarrow\)\(x+1=\sqrt{16}=4\)\(\Rightarrow\)\(x=4-1=3\)
Hoặc \(x+1=-\sqrt{16}=-4\)\(\Rightarrow\)\(x=-4-1=-5\)
Vậy \(x=3\) hoặc \(x=-5\)
Chúc bạn học tốt ~
\(\frac{7}{8}\)nha
__________________
__________________
^_^ hok tốt
x+1/2=8/x+1
=>(x+1)^2=2.8
=>(x+1)^2=16
=>(x+1)^2=4^2
=>x+1= 4 hoặc X+1=-4
đến đây rồi thì tự giải nhé
b, x:(9/1/2-3/20=0.4+2/9-2/11 // 1.6+8/9-8/11
x:(19/2-3/2)=2/5+2/9-2/11 // 8/5+8/9-8/11
x: 8= 2(1/5+1/9-1/11) // 8(1/5+1/9-1/11)
x:8=2/8
x=2/8.8
x=2