Complex Numbers practice, graded like a real exam
Arithmetic, the Argand plane, polar form and De Moivre. Complex Numbers rewards precision and repetition more than almost anything else on a foundations course — it is exactly the kind of topic where working through twenty varied problems beats re-reading the chapter a third time. QED gives you an endless supply of exam-grade complex numbers questions and marks every answer the way an examiner would, so each attempt actually teaches you something.
✓ First questions free · no card · no personal data stored
What a Complex Numbers question looks like
In a QED session, an exam-level complex numbers question might ask you to work through complex numbers problems at exam standard and get marked step by step.
Every question carries a hidden marking rubric. You answer in real notation, and QED marks each criterion separately — awarding partial credit and showing a full worked solution, so you learn from the marks you dropped.
Every Complex Numbers subtopic
13 focused guides, each with the method, a worked example and the mistakes that cost marks. Work through them in order or jump to your weak spot.
- 1The imaginary unit i & complex arithmetic
- 2Conjugates & division
- 3Modulus, argument & the Argand diagram
- 4Polar & exponential form re^{iθ}
- 5Multiplying & dividing in polar form
- 6De Moivre’s theorem & powers
- 7nth roots & roots of unity
- 8Solving polynomial equations over ℂ
- 9The fundamental theorem of algebra & conjugate roots
- 10Euler’s formula & trigonometric identities
- 11Loci & regions in the complex plane
- 12Complex multiplication as rotation & scaling
- 13Applications: phasors & AC circuits
Why students use QED for Complex Numbers
Not another chatbot that blesses whatever you type. QED is built for deliberate practice — the way maths actually sticks.
Practice that never runs out
A textbook gives you a handful of complex numbers exercises with the same worked answers everyone has seen. QED generates unlimited fresh complex numbers questions at warm-up, exam and challenge level, so you can drill a weak spot until it is automatic — not until you run out of problems.
Marked like an examiner, not a checkbox
Most tools just say “correct” or “wrong”. QED marks your complex numbers answer against a point-by-point rubric, awards partial credit, shows exactly where the reasoning slipped, and gives a full model solution. A right answer with the wrong argument still loses the argument marks — just like a real exam.
A library you can come back to
Every complex numbers question you generate is saved, organised and re-takeable as a timed exam. Your mastery is tracked per topic, so you always know whether Complex Numbers is exam-ready or still needs work — and you can export any question or exam report to PDF.
Write maths the way you actually write it
Answer in real notation with a one-tap symbol palette and a visual equation editor, drop in truth tables, or photograph a handwritten page — QED converts your handwriting to clean LaTeX. No fighting with syntax to show what you know.
How practising Complex Numbers works
- Generate a fresh questionPick Complex Numbers and a difficulty — warm-up to build intuition, exam level for the real thing, or challenge for multi-step problems. A new, verified question appears in seconds.
- Answer in real notationType it, build it in the equation editor, lay out a truth table, or photograph your handwritten working and let QED convert it to LaTeX.
- Get marked criterion by criterionQED scores every rubric point separately, awards partial credit, flags where the reasoning slipped and shows a full model solution. The question is saved to your library to retake any time.
Related topics
Building a full picture of foundations? These pair naturally with Complex Numbers.
Complex Numbers — frequently asked questions
Is QED good for revising Complex Numbers before an exam?
Yes — that is exactly what it is built for. Generate complex numbers questions at exam level (or push up to challenge), answer them under timed exam mode, and get marked against a rubric with a full model solution. You can retake any question and watch your Complex Numbers mastery climb until it is solid.
How many Complex Numbers questions can I practise?
As many as you like. QED generates fresh complex numbers problems on demand instead of recycling a fixed set, and every question you make is saved to your library to retake for free. New accounts start with free question generations, no card required.
Do I need to know LaTeX to answer Complex Numbers questions?
No. There is a one-tap palette for symbols, a visual equation editor, and a truth-table builder — and you can photograph a handwritten solution and let QED convert it to LaTeX for you. You concentrate on the maths, not the typesetting.
Ready to make Complex Numbers exam-proof?
Generate your first complex numbers questions free — no card, no setup, no personal data stored. Practise until it is second nature.
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