Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
$\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\ldots \ldots \ldots+\ldots \ldots \cdot \frac{1}{n \cdot(n+1)}$
MathematicsSequences and SeriesJEE Main
Options:
  • A $\frac{1}{n(n+1)}$
  • B $\frac{n}{n+1}$
  • C $\frac{2 n}{n+1}$
  • D $\frac{2}{n(n+1)}$
Solution:
2612 Upvotes Verified Answer
The correct answer is: $\frac{n}{n+1}$
$\left(\frac{1}{1}-\frac{1}{2}\right)+\left(\frac{1}{2}-\frac{1}{3}\right)+\left(\frac{1}{3}-\frac{1}{4}\right)+\ldots \ldots \ldots+\left(\frac{1}{n}-\frac{1}{n+1}\right)$
$=1-\frac{1}{n+1}=\frac{n}{n+1}$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.