Question

BT1: Tính:

1) | \(\frac{-1}{7}\) + \(\frac{-4}{3}\) | + \(\frac{-5}{2}\)

2) \(\frac{-3}{2}\) + | \(\frac{-4}{7}\) | + | \(\frac{-1}{5}\)

Answer 1

1) \(\left|\dfrac{-1}{7}+\dfrac{-4}{3}\right|+\dfrac{-5}{2}\)

\(=\left|\dfrac{-31}{21}\right|+\dfrac{-5}{2}\)

\(=\dfrac{31}{21}+\dfrac{-5}{2}=\dfrac{-43}{42}.\)

2) \(\dfrac{-3}{2}+\left|\dfrac{-4}{7}\right|+\left|\dfrac{-1}{5}\right|\)

\(=\dfrac{-3}{2}+\dfrac{4}{7}+\dfrac{1}{5}\)

\(=\dfrac{-51}{70}.\)

Answer 2

1) \(\left|\dfrac{-1}{7}+\dfrac{-4}{3}\right|+\dfrac{-5}{2}\)

= \(\left|\dfrac{-3}{21}+\dfrac{-28}{21}\right|+\dfrac{-5}{2}\)

= \(\left|\dfrac{-31}{21}\right|+\dfrac{-5}{2}\)

= \(\dfrac{31}{21}+\dfrac{-5}{2}\)

= \(\dfrac{62}{42}\)+\(\dfrac{-105}{42}\)

= \(\dfrac{-43}{42}\)

Answer 3

| là dấu gì zậy bn

Answer 4

2) \(\dfrac{-3}{2}+\left|\dfrac{-4}{7}\right|+\left|\dfrac{-1}{5}\right|\)

= \(\dfrac{-3}{2}+\dfrac{4}{7}+\dfrac{1}{5}\)

= \(\dfrac{-105}{70}+\dfrac{40}{70}+\dfrac{14}{70}\)

= \(\dfrac{-51}{70}\)