|WikiProject Mathematics||(Rated Start-class, Low-importance)|
- Edit conflict. I added the stubnote you had put in from the top window, but didn't see that you had also added an article at the beginning of the article. So yes, keep "a" in. Wiwaxia 11:37, 28 Apr 2004 (UTC)
1-dimensional or 2-dimensional?
This article presents just one use of the word semicircle, namely, as a synonym to "half-disc". The article is a bit unclear in this and some other points; it claims that this two-dimensional item "forms half of a circle"; but mathematicians in general define a circle to be 1-dimensional. There is also a mentioning of "any triangle inscribed in a semicircle"; what is meant is however something more restricted.
- I agree, article looks inconsistent, confusing half-disc for semicircle.--220.127.116.11 (talk) 07:32, 15 June 2011 (UTC)
A triangle inscribed in a semicircle is always a right triangle.
I removed the comment "A triangle inscribed in a semicircle is always a right triangle." from the first paragraph. I think it is clearly wrong, however the person who wrote this may be thinking of something else. So, I am at least making an effort to make a comment here. John W. Nicholson (talk) 01:32, 10 January 2013 (UTC)
- Clearly, an equilateral triangle (or other triangles) can be made with one point on the diameter and two points on the arc length. Maybe this: Thales' theorem states that if A is any point of the circle with diameter BC (except B or C themselves) ABC is a right triangle where A is the right angle. John W. Nicholson (talk) 01:45, 10 January 2013 (UTC)