Question

Answer 1

Bài này có 2 trường hợp nha

Answer 2

b: Trường hợp 1: x=0,5

\(B=5\cdot\dfrac{1}{2}-7\cdot\left|\dfrac{1}{5}\cdot\dfrac{1}{2}-5\right|+3\cdot\left|\dfrac{1}{2}\right|-1\)

\(=\dfrac{5}{2}-7\cdot\dfrac{49}{10}+\dfrac{3}{2}-1\)

\(=3-\dfrac{343}{10}=\dfrac{-313}{10}\)

Trường hợp 2: x=-0,5

\(B=5\cdot\dfrac{-1}{2}-7\cdot\left|\dfrac{1}{5}\cdot\dfrac{-1}{2}-5\right|+3\cdot\left|\dfrac{-1}{2}\right|-1\)

\(=\dfrac{-5}{2}+\dfrac{3}{2}-1-7\cdot\dfrac{51}{10}\)

\(=-2-\dfrac{357}{10}=\dfrac{-377}{10}\)