Файл:Archimedean-involute-circle-spirals-comparison.svg

Comparison of the Archimedean spiral generated by the equations x=θcosθ and y=θsinθ with the Involute of a circle, generated by the equations x=cosθ+θsinθ and y=sinθ-θcosθ (where "θ" is an angle expressed in radians). The Archimedean spiral is shown in red, and corresponds to the values 0 ≤ θ ≤ 8π of the angle parameter, while the Involute of the circle is shown in black, and corresponds to the values 0 ≤ θ ≤ 17π/2 of the angle parameter. The x-axis extends from -25 to +28 and the y-axis from -26.4 to +23.4, and there are tick marks at -20, -10, +10, +20 along the axes.

The curves are 1 unit apart at their start points, while they are slightly more than 1.5 (and slightly less than π/2) units apart where they intersect the x-axis for the final time in this plot.

Self-made graphic converted from the following vector PostScript source code:

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