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We put the 'fun' in function (Posted on 2003-07-01) Difficulty: 4 of 5
Consider the function f(x)=ln(x)/√x
  1. Find the limit of f as x → 0 from the positive side.
  2. Find f(-1). Hint: f(-1)>0

  Submitted by Bryan    
Rating: 4.0000 (2 votes)
Solution: (Hide)
For the first part, as x → 0 from the positive side, ln(x)/√x → -infinity/0 (0 from the + side). This is not indeterminate, so don't try L'Hopital's rule here. Both the numerator and the denominator drive f to -infinity.

For the second part, let y=f(x). For x=-1,

y=ln(-1)/i
iy=ln(-1)
e^iy=-1

From this arrangement, we see that y=pi (Euler's law).

Comments: ( You must be logged in to post comments.)
  Subject Author Date
AnswerK Sengupta2008-11-16 00:39:44
Solutionsolutionlmnop2004-05-27 02:12:31
Love those transcendentals!mathemagician2003-07-04 13:32:00
SolutionsolutionCharlie2003-07-01 03:00:44
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