Complex Numbers and Quadratic Equations

🕒 Previous Year Questions Stats

Total Questions
Easy Questions
Medium Questions
Hard Questions
12
0
6
6

📚 Key Concepts

  • Complex numbers (a + bi)
  • Imaginary unit i (i² = -1)
  • Algebra of complex numbers
  • Geometric representation (Argand plane)
  • Modulus and argument
  • Conjugate of complex numbers
  • Polar representation
  • Quadratic equations with complex roots
  • 🎯 Key Formulas

  • For complex numbers z = a + bi:
    • Modulus: |z| = √(a² + b²)
    • Conjugate: z̄ = a - bi
    • Argument: arg(z) = tan⁻¹(b/a)
  • Powers of i:
    • i² = -1
    • i³ = -i
    • i⁴ = 1
  • Polar form: r(cosθ + i sinθ)
  • If α + iβ is a root, then α - iβ is also a root
  • ⚠️ Common Mistakes to Avoid

  • Forgetting i² = -1 while simplifying
  • Wrong modulus calculation
  • Incorrect conjugate usage
  • Errors in polar representation
  • Mistakes in argument calculation
  • Wrong application of complex roots in quadratic equations
  • 📖 Knowledge Prerequisites

  • Real numbers
  • Quadratic equations
  • Basic algebra
  • Coordinate geometry
  • Trigonometry basics
  • 💡 Tips for Students

  • Practice i powers pattern
  • Always check conjugate pairs in roots
  • Use Argand plane for visualization
  • Remember complex number properties
  • Master basic operations first
  • 👉 Practice Recommedations

  • Simplify complex expressions
  • Find modulus and arguments
  • Convert between forms (algebraic/polar)
  • Solve quadratic equations
  • Practice geometric representation
  • Work with conjugates
  • Apply in polynomial problems
  • Practice each question with a timer and get instant feedback
    📢 Rank Predictor-Mock Test 1 is Live now & its FREE! 📢 Mock Test 1 is Live & Free now!