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Lesson Packs · Grade 12 · Mathematics

Complex Numbers

Students meet the imaginary unit i, calculate with complex numbers in the form a + bi (including division with the conjugate), plot them on an Argand diagram, find the modulus, argument and polar form, and solve quadratics with a negative discriminant.

Unit 8 · Lesson 24 · Complex Numbers and Matrices

Preview

Complex Numbers — Slide 1
  • Complex Numbers — Slide 4
    Slide 4
  • Complex Numbers — Slide 7
    Slide 7
  • Complex Numbers — Slide 17
    Slide 17
  • Complex Numbers — Slide 18
    Slide 18
  • Complex Numbers — Worksheet, page 1
    Worksheet, page 1
  • Complex Numbers — Answer key, page 1
    Answer key, page 1

Learning objectives

  • Use i² = −1 to simplify powers of i and to add, subtract, multiply and divide complex numbers.
  • Represent complex numbers on an Argand diagram and find their modulus, argument and polar form.
  • Solve quadratic equations that have a negative discriminant.

What's inside

  • 40 PowerPoint slides: lesson, worked examples and the worksheet with solutions
  • 11 worksheet questions (34 marks) with step-by-step solutions
  • Printable worksheet (4 pages) and a teacher answer key
  • Fully editable in PowerPoint, Google Slides, Keynote and Word

More lessons in this unit

Questions teachers ask

Can I edit the files?

Yes. The PowerPoint and the Word worksheet are fully editable, so you can change examples, add questions or adapt the design for your class.

How do I use the worksheet slides?

After the teaching slides, each worksheet question appears on its own slide. Let students try it first, then show the next slide and work through the solution together.

Is there an answer key?

Yes. The Word file ends with a teacher answer key that has the answer and a worked solution for every question. It is also included as a separate PDF.

Which languages are available?

Every Lesson Pack is made in 18 languages: English, Simplified Chinese, Hindi, Spanish, Arabic, French, Bengali, Portuguese, Indonesian, Urdu, Vietnamese, Albanian, Italian, German, Turkish, Malay, Greek and Traditional Chinese (Hong Kong).

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