WOLFRAM|DEMONSTRATIONS PROJECT

Tangent on a Logarithmic Spiral

​
c
1
a
0.3
θ
-1.0472
leg of triangle
1
The logarithmic spiral
r=c
aθ
e
has the property that the angle (say
α
) between a radius vector to a point on the curve and the tangent at the point is a constant, namely
tan(α)=1/a
.