Math CentralQuandaries & Queries


Question from Nazrul, a teacher:

Is zero degree an acute angle? Please explain.

I would say a zero degree angle is an acute angle for the following reasons:

  • A zero degree angle is formed by two rays that share a vertex and point in the same direction.
  • According to Euclid's Elements, Book I, Definition 12. "An acute angle is an angle less than a right angle."

Hope this helps,


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