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April 29th, 2018, 02:12 PM   #1
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Angles Not Between 0 and 360

Hi!

For one of the questions for geometry I have to name and give examples of 2 types of angles that are not between 0 and 360 degrees. I cannot find what these angles are called anywhere! Anyone have any suggestions?
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April 29th, 2018, 02:22 PM   #2
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Originally Posted by Indigo28 View Post
Hi!

For one of the questions for geometry I have to name and give examples of 2 types of angles that are not between 0 and 360 degrees. I cannot find what these angles are called anywhere! Anyone have any suggestions?
Don't give us much context to go on do you?

How about calculating the number of degrees a shaft revolving at 3000 rpm would turn per second?

But you did mention geometry so how about an angle of 390 grads?

Or perhaps the number of degrees of the four spherical triangles whose vertices meet at a point on the equator and whose other sides point North and East, North and West, South and East, South and West add up to round the point?

Last edited by studiot; April 29th, 2018 at 02:41 PM.
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April 29th, 2018, 02:32 PM   #3
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I don't give much context to go on, because I wasn't given any more information than that! I'm going back through my lessons but don't see anything about it.

Thank you for your suggestions!
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April 29th, 2018, 06:07 PM   #4
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Originally Posted by Indigo28 View Post
For one of the questions for geometry I have to name and give examples of 2 types of angles that are not between 0 and 360 degrees.
0 degrees and 360 degrees are not between 0 and 360 degrees
0[1,2,3......358,359]360
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April 30th, 2018, 12:14 AM   #5
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Originally Posted by Denis View Post
0 degrees and 360 degrees are not between 0 and 360 degrees
0[1,2,3......358,359]360
Moral lesson by Denis McField: Always try to think literal first to approach a problem
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April 30th, 2018, 02:23 AM   #6
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Actually I fluffed the explanation of the third offer in my last post since the angles round a point still add up to 360.

The thing I was trying to get over is called spherical excess, which for the triangles I mentioned is 90 degrees, making the total angles for each of those triangles 270.
So, of course four such triangles contain 4*270 = 1080 degrees.

Anyway here are two more offerings.

The given range shows positive angles, which (presumably) conform to the conventional direction of angle specification.

Simple reversing this direction allows -10 degrees to be outside the given range.



arcsin (3) is a complex number {1.57 + 1.76i} which is also ouside the given range
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