Conjugate and Modulus Squared (z̄ = x − iy; z·z̄ = |z|²)

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z̄ = x − iy; z·z̄ = |z|²

What each symbol means

SymbolWhat it stands for
Complex conjugate of z = x + iy
z z̄Product z·z̄ = x² + y² = |z|² (always real and ≥ 0)

When to use this

For z = x + iy ∈ ℂ. Used to rationalize denominators and compute |z|² without square root.