Complex numbers · AS 91577
Apply the algebra of complex numbers in solving problems
Apply the algebra of complex numbers in solving problems
This standard asks you to work with complex numbers — numbers that have both real and imaginary parts — and use algebra to solve problems with them. You'll need to convert between different forms, find arguments and moduli, apply important theorems, and check which solutions are actually valid. It's about using mathematical techniques confidently and showing your working clearly so examiners can see your reasoning.
You can manipulate complex numbers in both forms, apply the quadratic formula or complete the square, find moduli and arguments correctly, apply de Moivre's theorem, and simplify expressions by grouping real and imaginary parts.
You solve equations involving surds and complex numbers then check which solutions are actually valid, understand why the modulus is always positive, find all solutions using de Moivre's theorem, and can work with cubic polynomials when given one imaginary root.
You manipulate quotients and complex equations with precision and clarity, solve multi-step problems by correctly grouping real and imaginary parts, communicate your thinking step-by-step throughout, recognise when a strategy isn't working and adjust, and prove statements by making connections between the real and imaginary parts.
Standards typically taken alongside or after this one. Same subject, grouped by level.