WisFaq!

Cirkel in 5 gelijke delen

Hoe deel je een cirkel in 5 gelijke delen? (Het moet met passer en liniaal gebeuren)

Imp
20-7-2001

Antwoord

Construction of a regular pentagon:

Let N,S,E,W be the points of a circle C with center O in the four compass directions, and let M be the midpoint of ON.

Let E' and E" be the points where the circle with center M through E meets the line NS.

Finally, let P' and P" be the points where the circle with center E through E' meets C and let Q' and Q" be the points where the circle withcenter E through E" meets C.

Then E, P', P", Q' and Q" form a regular pentagon.

Zie Bron [http://mathforum.com/dr.math/faq/formulas/faq.regpoly.html]

WvR
20-7-2001