Tabellab
Math & Teaching Intermediate

Complex Numbers in Spreadsheets: Rectangular & Polar Form, Arithmetic, Powers & Roots, Rotations and AC Phasors

Make complex numbers concrete with two columns. You will add, multiply and divide numbers written as real and imaginary parts, convert to modulus and angle, multiply in polar form, raise to powers and take roots with De Moivre, rotate shapes in the plane and solve simple AC circuits with phasors, with every cell checked as you go.

8 lessons 8 labs 2.1 h Certificate

One-time payment · lifetime access · lessons, labs, exam and certificate included · no subscription.

About this course

This course keeps every complex number in two spreadsheet columns, one for the real part and one for the imaginary part, so each step is a formula you can read. You plot numbers on the complex plane, write conjugates and multiply out products and quotients by hand. You compute modulus and argument with SQRT and ATAN plus a quadrant correction, switch between rectangular and polar form, and raise numbers to powers and take n-th roots with De Moivre's rule. Then you rotate and scale a shape by one multiplication, solve quadratic equations with complex roots and check them by substitution, and finish with impedances, phase angles and currents in fictional AC circuits.

Lessons

  1. The Complex Plane: Real & Imaginary Columns, Quadrants and ConjugatesLab14 min Pro
  2. Complex Arithmetic: Sums, Products (ac − bd, ad + bc) and Division by the ConjugateLab15 min Pro
  3. Modulus & Argument: Distances, ATAN with a Quadrant Correction, Degrees vs RadiansLab16 min Pro
  4. Polar Form: r(cos θ + i sin θ), Multiplying Moduli and Adding AnglesLab15 min Pro
  5. Powers & Roots: De Moivre's Rule, n-th Roots and the Roots of UnityLab17 min Pro
  6. Rotations & Scaling: Multiplying a Shape by a Complex NumberLab16 min Pro
  7. Quadratic Equations: Negative Discriminants, Complex Root Pairs and Checking by SubstitutionLab16 min Pro
  8. AC Phasors: Impedance R + jX in Series and Parallel, Current Magnitude and Phase AngleLab18 min Pro