Complex numbers

Build and connect the representations and methods in complex numbers.

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  • 2 lessons
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Before you begin

Build and connect the representations and methods in complex numbers.

Learning goals
  • Add complex numbers
  • Subtract complex numbers
  • Multiply complex numbers
  • Divide by a nonzero complex number
  • Find the conjugate of a complex number
  • Find every distinct root of a real quadratic over the complex numbers
  • Solve a unique linear complex equation, including a conjugate term
  • Recover the remaining distinct roots of a real cubic or quartic from a non-real root
  • Explain complex equality, the number system and real-coefficient root properties
  • Calculate the modulus of a complex number
  • Calculate a complex number's principal argument
  • Represent and explain complex operations on an Argand diagram
Syllabus statements covered
  • Include: extending real numbers to complex numbers; complex roots of quadratic equations; modulus, argument and conjugate; four operations; equality; conjugate roots of real-coefficient polynomials; Argand diagrams; geometrical effects of conjugation, negation, addition, subtraction and multiplication by i. Exclude polar or modulus-argument and exponential forms.
  • Include: extending real numbers to complex numbers; complex roots of quadratic equations; modulus, argument and conjugate; four operations; equality; conjugate roots of real-coefficient polynomials; Argand diagrams; geometrical effects of conjugation, negation, addition, subtraction and multiplication by i. Exclude polar or modulus-argument and exponential forms.

Lessons

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