Last Updated Sep 27, 2025

Dividing Simplified Revision Notes for Leaving Cert Mathematics

Revision notes with simplified explanations to understand Dividing quickly and effectively.

Learn about The Basics for your Leaving Cert Mathematics Exam. This Revision Note includes a summary of The Basics for easy recall in your Mathematics exam

362+ students studying

The Basics Quizzes

Test your knowledge with quizzes.

The Basics Flashcards

Practice with bite-sized questions.

The Basics Questions by Topic

Prepare with real exam question.

Print Free PDF

Dividing

To divide complex numbers, we eliminate the imaginary part from the denominator by multiplying the numerator and denominator by the conjugate of the denominator.

Example

infoNote

Simplify the following :

$$\frac{1+i}{2+i}$$

---

First, derive the conjugate of the denominator, $\overline{2+i}=2-i$.

$$\begin{align*} \frac{1+i}{2+i}&=\frac{1+i}{2+i}\cdot \frac{2-i}{2-i} \\\\ &= \frac{2-i+2i-i^2}{4-2i+2i-i^2} \\\\ &=\frac{2-i+2i-(-1)}{4-2i+2i-(-1)} \\\\ &=\frac{3+i}{5} \end{align*}$$

Write in the form $a+bi$ :

$$\begin{align*} \frac{3+i}{5}&=\frac{3}{5}+\frac{1}{5}i \end{align*}$$

infoNote

In all cases, multiplying a complex number $z$ with it's conjugate $\overline{z}$ will eliminate the imaginary component.

Only available for registered users.

Sign up now to view the full note, or log in if you already have an account!

Sign up with GoogleSign up with Apple

500K+ Students Use These Powerful Tools to Master Dividing For their Leaving Cert Exams.

Enhance your understanding with flashcards, quizzes, and exams—designed to help you grasp key concepts, reinforce learning, and master any topic with confidence!

Other Revision Notes related to Dividing you should explore

Discover More Revision Notes Related to Dividing to Deepen Your Understanding and Improve Your Mastery

96%

114 rated

The Basics

Definition

377+ studying

194KViews

View Note

96%

114 rated

The Basics

Adding & Subtracting

376+ studying

190KViews

View Note

96%

114 rated

The Basics

Conjugates

317+ studying

181KViews

View Note

96%

114 rated

The Basics

Multiplying

494+ studying

186KViews

View Note