infinity?

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2 total messages Started by Mark Fleharty Fri, 22 Jan 1993 03:48

#1009

Author: Mark Fleharty
Date: Fri, 22 Jan 1993 03:48

16 lines
784 bytes


I know that tan of 90 is considered undefined but could it be infinity?

Also if 8/4 = 2 and 2*4 = 8 couldn't it work with zero too?

Ex.  If x = 2/0 would x*0 = 2?
or would that = 0?

Just out of curiosity.

Mark Fleharty
scc26mf@carina.unm.edu 

-----------------------
"People who are always board are boring people."

Re: infinity?

#1033

Author: Sadasivan Shankar
Date: Fri, 22 Jan 1993 17:25

22 lines
1444 bytes

Dividing by zero is not defined.  It is not pssible to compare dividing by a real number and
divind by zero.  If you look at the definition of functional spaces, for instance, multiplying
by zero itself is defined  as a separate operation.  Although tan (90) may not be defined
in this sense, cotangen (90) = 0.  Tangent-type functions (including) Cotangent are functions
with infinite discontinuties.  One way to see why tan (90) can't really be said to be
infinity is can be seen from the following example.

	Tan (0) = 0
	Tan (pi/4) = 1.
	Tan (90)_ = ?
	Tan  (90 + theta) = - cotangent (theta)

Thus to the right of pi/2 (in the period 0 - 2*pi), the tangent function starts from - (negative) Large
values.  Thus at pi/2, it is not exactly defined, since it could be +inf (approaching it from
left) or -inf (approaching it from right). Hope that this answers some of your questions.
	
S.Shankar
Tech CAD
INTEL

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