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slope of a curve

slope of a line

Figure 2: Straight lines (see text).

A diagram illustrating projective geometry duality, showing a point labeled P and a line labeled RS intersecting at an oval shape, with arrows indicating the association between point P and line RS.

The French mathematician René Descartes (1596–1650) demonstrated that the square root of any line segment could be constructed by the simple, but ingenious, addition of a line segment with unit length.

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Topics

Sylvester’s problem parallel lines length curve conic section catenary spiral orthogonal trajectory Lissajous figure curvature foundations of mathematics probability and statistics numerals and numeral systems matrix function fractal graph derivative algorithm vector

Key People

Plücker, Julius

Julius Plücker

German mathematician and physicist