Question

timx 

5x*(2x-1/2) + 2*(2x-1/2)=0

Answer 1

\(5x\times\left(2x-\frac{1}{2}\right)+2\times\left(2x-\frac{1}{2}\right)=0\)

\(\Rightarrow\left(2x-\frac{1}{2}\right)\left(5x+2\right)=0\)

\(\Rightarrow\orbr{\begin{cases}2x-\frac{1}{2}=0\\5x+2=0\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}\frac{1}{4}\\x=\frac{-2}{5}\end{cases}}\)

Answer 2

Ta có 5x.(2x-1/2)+2.(2x-1/2)=0

        = (2x-1/2)(5x+2)=0

       Suy ra 2x-1/2=0 hoặc 5x+2=0

      Vậy x=1/4 hoặc x=-2/5

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