Question

Tìm các số nguyên x , sao cho :

                               \(\dfrac{2}{x}=\dfrac{x}{8}\)

Answer 1

Answer 2

\(\text{Ta có:}\dfrac{x}{8}=\dfrac{2}{x}\)

\(\Rightarrow\dfrac{x}{8}.8x=\dfrac{2}{x}.8x\)

\(\Rightarrow x^2=16\)

\(\Rightarrow\left[{}\begin{matrix}x^2=\left(-4\right)^2\\x^2=4^2\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=-4^{ }\\x^{ }=4^{ }\end{matrix}\right.\)

\(\text{Vậy }x\in\left\{-4;4\right\}\)

 

Answer 3

\(\dfrac{2}{x}=\dfrac{x}{8}\)

nên \(x^2=16\)

hay \(x\in\left\{4;-4\right\}\)

Answer 4

Ta có 2/x=x/8 ->x.x=2.8->x mũ 2=16 <-> x=4 hoặc x=-4