Circle has infinite sides how many sides does a semi circle have?

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Discussion Overview

The discussion revolves around the concept of how many sides a semicircle has, particularly in relation to the idea that a circle has infinite sides. Participants explore the implications of defining sides in geometric terms and the analogies drawn from regular polygons.

Discussion Character

  • Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions the validity of dividing infinity by two to determine the sides of a semicircle, suggesting that infinity is not a number.
  • Another participant explains that a circle is considered to have infinitely many sides based on the analogy with regular polygons, proposing that one could similarly analyze the sides of a semicircle by halving regular polygons.
  • A different viewpoint suggests that any curve can be interpreted as having an infinite number of 'sides' with lengths approaching zero.
  • One participant humorously states that a circle has two sides: the inside and the outside, indicating a light-hearted take on the topic.

Areas of Agreement / Disagreement

Participants express differing views on the definition of sides in relation to circles and semicircles, indicating that the discussion remains unresolved with multiple competing interpretations.

Contextual Notes

The discussion highlights limitations in the definitions of geometric concepts and the assumptions underlying the analogy with polygons, but does not resolve these issues.

Noj Werdna
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If a circle has infinite sides how many sides does a semi circle have?
i have asked my teachers at school but they have ll said u wud have 2 divide infinity by 2 and +1 which obviously isn't possible cos infinity isn't reli a number is it...

Thanks
 
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A circle is said to have infinitely many "sides" due to the analogy with regular polygons.
(i.e. a triangle has 3, a square 4, and so on)
Eventually you get a shape with so many sides that it "becomes" a circle.
If you want to find how many "sides" a semicircle has, just continue in the same way...
Cut regular polygons in half and work out how many sides they have
(i.e. half a triangle has 3 sides half a square has 4, half a pentagon... etc)

Do you see the idea?

(It's just a bad/weird definition of a circle, since it doesn't really have sides, does it?)
 


Any curve can be looked at as having an infinite number of 'sides' whose length goes to zero, no matter how big.
 


there are two sides to a circle - inside and outside. (posted lest someone begin to take this more seriously than the topic deserves)
 

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