2022 DHS Promo Q2

Solved by

Timothy Gan

This is Tim. Tim loves to teach math. Tim seeks to improve his teaching incessantly! Help Tim by telling him how he can do better.
2022 DHS Promo Q2

(a)

Given that $\text{f}$ is a continuous and increasing function, explain, with an aid of a sketch, why the value of 

$\underset{n\to \infty }{\mathop{\lim }}\,\frac{2}{n}\left[ \text{f}\left( 1 \right)+\text{f}\left( 1+\frac{2}{n} \right)+\text{f}\left( 1+\frac{4}{n} \right)+…+\text{f}\left( 1+\frac{2\left( n-1 \right)}{n} \right) \right]$

is $\int_{1}^{3}{\text{f}\left( x \right)}\,\text{d}x$.

[2]

(b)

Hence, evaluate $\underset{n\to \infty }{\mathop{\lim }}\,\frac{2}{n}\left( {{\text{e}}^{2}}+{{\text{e}}^{2+\frac{4}{n}}}+{{\text{e}}^{2+\frac{8}{n}}}+…+{{\text{e}}^{2+\frac{4\left( n-1 \right)}{n}}} \right)$, leaving your answer in exact form.

[2]

Suggested Video Solutions

Students Only

Login here to view
Join Us

Our H2 Math Tuition includes

  • Question Bank with Video solutions to 1400+ questions
  • Online Portal
  • H2 Math Summary Notes
  • Structured Curriculum and Notes
Free Stuff

Share with your friends!

WhatsApp
Telegram
Facebook
Continue reading

Published: 4th September 2023

Leave a Reply

Your email address will not be published. Required fields are marked *