Question

2x-1/4 - 2x+1/5 < 1/2

Answer 1

Ta có: \(\dfrac{2x-1}{4}-\dfrac{2x+1}{5}< \dfrac{1}{2}\)

\(\Leftrightarrow\dfrac{5\left(2x-1\right)}{20}-\dfrac{4\left(2x+1\right)}{20}< \dfrac{10}{20}\)

Suy ra: \(10x-5-8x-4< 10\)

\(\Leftrightarrow2x< 19\)

hay \(x< \dfrac{19}{2}\)

Vậy: S={x|\(x< \dfrac{19}{2}\)}

Answer 2

\(\dfrac{2x-1}{4}-\dfrac{2x+1}{5}< \dfrac{1}{2}\)

\(\Leftrightarrow\dfrac{10x-5-8x-4}{20}< \dfrac{10}{20}\Rightarrow2x-9< 10\Leftrightarrow x< \dfrac{19}{2}\)

Vậy tập nghiệm BFT là S = { x | x < 19/2 }