\(\dfrac{x}{2}=\dfrac{8}{x}\\ =>x^2=2.8=16\\ Mà:\left[{}\begin{matrix}4^2=16\\\left(-4\right)^2=16\end{matrix}\right.\\ =>\left[{}\begin{matrix}x^2=4^2\\x^2=\left(-4\right)^2\end{matrix}\right.=>\left[{}\begin{matrix}x=4\\x=-4\end{matrix}\right.\)
Vậy: x= 4 hoặc x=-4
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\(\dfrac{x}{2}=\dfrac{8}{x}\)
=> x.x=8.2
=> x2=16
=> x2=42
=> x=4
Vậy x=4
\(\dfrac{x}{2}=\dfrac{8}{x}\)
\(\Rightarrow x.x=8.2\)
\(\Rightarrow x^2=16\)
\(\Rightarrow x^2=4^2\) hay \(x^2=\left(-4\right)^2\)
\(\Rightarrow x=4\) hay \(x=-4\)
Vậy \(x\in\left\{4;-4\right\}\)
\(\dfrac{x}{2}\)=\(\dfrac{8}{x}\)\(\Rightarrow\)(x.x)=8.2
x2=16
x2=(\(\pm\)4)2
\(\Rightarrow\)\(\left\{{}\begin{matrix}x=4\\x=-4\end{matrix}\right.\)
Vậy x=4 hoặc x=-4
\(\dfrac{x}{2}=\dfrac{8}{x}\)
=> x . x = 2 . 8
=> x\(^2\) = 16
=> x\(^2\) = 4\(^2\)
=> x = 4