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Math Forum » Discussions » Math Topics » alt.math.recreational.independent

Topic: Why can I draw a triangle with two 90 degree angles and one 0 degree angle?
Replies: 8   Last Post: Jul 26, 2010 2:28 PM

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McTernan, James

Posts: 1
Registered: 6/22/10
Re: Why can I draw a triangle with two 90 degree angles and one 0 degree angle?
Posted: Jun 22, 2010 2:59 PM
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You used the phrase "take the limit" very easily...

I thought the whole point of limits is that you may never be able to reach the value. Your triangle may become slimmer and slimmer, arbitrarily close to the ideal 90-90-0 triangle; but if you ever just set an angle to zero, your figure is "undefined", or at least controversial. You can only say that your angle can become smaller than any positive number.

This is the same thing that happens in the definition of the derivative. Delta can become arbitrarily close to zero, but setting it to zero makes the expression meaningless.

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