Question

\(\dfrac{1}{30}\) + \(\dfrac{1}{42}\) +\(\dfrac{1}{56}\) + ... + \(\dfrac{1}{600}\) 

giúp mình giải bài này với

Answer 1

\(=\dfrac{1}{5.6}+\dfrac{1}{6.7}+\dfrac{1}{7.8}+...+\dfrac{1}{24.25}\)

\(=\dfrac{1}{5}-\dfrac{1}{6}+\dfrac{1}{6}-\dfrac{1}{7}+...+\dfrac{1}{24}-\dfrac{1}{25}\)

\(=\dfrac{1}{5}-\dfrac{1}{25}=\dfrac{4}{25}\)