Euler's formula

Definitions

1. A formula which links complex exponentiation with trigonometric functions
2. A formula which calculates the normal curvature of an arbitrary direction in the tangent plane in terms of the principal curvatures κ₁ and κ₂ and the angle θ which that direction makes with the first principal direction

Equivalents

Examples

“eⁱᶿ= cos θ+i sin θ”

“κₙ(θ)=κ₁ cos ²θ+κ₂ sin ²θ”

CEFR level