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

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A circle is considered to have infinitely many sides based on the analogy with regular polygons, where shapes with more sides approximate a circle. The discussion raises the question of how many sides a semicircle has, suggesting that one could analyze this by halving regular polygons. However, the concept of "sides" for curves is debated, as circles do not have traditional sides. Ultimately, the idea of dividing infinity is flawed, as infinity is not a number. The conversation highlights the complexities of defining geometric shapes and the limitations of applying polygonal concepts to curves.
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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)
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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