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tan(PI/2) = ?

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• Anonymous at 2004-12-14 19:15
  What does tan(90 degrees) equal?
  
  My friend says its +infinity, i say its undefined. What do you think, Ken, since youre quite good at math ;) ?
• fantasio at 2004-12-14 19:38
  tan (90 degrees) is undefined.
  You can proof it in many different ways - here is my way:
  tan x = sin x / cos x (take a look at the unit circle to understand that)
  tan 90
  Edited at 2004-12-14 19:47
• Anonymous at 2004-12-14 19:42

  We don't need Ken to answer that question (sorry Ken :P):
  tan (90 degrees) is +infinity.
  You can proof it in many different ways - here is my way:
  tan x = sin x / cos x (take a look at the unit circle to understand that)
  tan 90

• Awesoken at 2004-12-15 05:30
  This is one of those stupid math questions where the answer depends on your faith - meaning you choose whatever definition you like the best. Since the C library is my god, this would be my answer:
  
  tan(PI/2) = 1.63318e+016 (double precision floating point)
  1.0/0.0 = 1.#INF00 (double precision floating point)
  1/0 = <crash> (32-bit integer)
  Edited at 2004-12-15 15:20
• counting_pine at 2004-12-15 09:12
  Perhaps it's worth mentioning that if you round pi down, you get a positive answer, while if you round it up you get a negative answer.
  
  tan(3.1415926535/2) = 2.22734e+010
  tan(3.1415926536/2) = -1.95947e+011
• cragtek at 2004-12-15 10:47

  Re: tan(PI/2) = ?

  What does tan(90 degrees) equal?
  
  My friend says its +infinity, i say its undefined. What do you think, Ken, since youre quite good at math ;) ?

  You must have some fascinating conversations.
• BarrenSoul at 2004-12-15 11:32

  tan(PI/2) = ?

  http://mathworld.wolfram.com/DivisionbyZero.html
  
  Read and learn, division by zero does exist :) but normaly no it dosn't.
• FreeDOSfan at 2005-03-04 18:26

  Illegal division by Zero :D

  "tan(pi/2)" is exactly the same as "1/0".
  
  Math correct: it is undefined.
  
  One could say: it is +infinity AND -infinity.
  
  If your math or problem is limited to positive numbers & 0, then it is +infinity only.
  
  See the func graph.
• Anonymous at 2005-03-06 05:53

  tan(PI/2) = ?

  Answer: graph it!!!
  
  http://img.photobucket.com/albums/v51/BarrenSoul/tanx.png
  
  and now for todays daily math lesson:
  
  notice the red arrows, what are these pointing at? answer: asymptotes (this is when a graph shows that it is tending towards a number but never hits it)
  
  and now for a calculus lesson:
  
  lets take a formula: F(x)=1/x
  
  now lets take the limits of this formula from both sides (if you don't know what a limit is don't worry to much)
  
  lim F(x)=0
  X->inf
  
  (note: without a limite F(x) can never be defined since it never =0)
  
  lim F(x)=DNE
  x->0
  
  so why does x->0 not exist? because it is tending to infinity negatively on one side and positively on the other, thus there is no intersection. some may be tempted to call this a point of discontinuity (a break in the line of a function) but thats not the true ex.:
  
  lim X^2-3X-18 = -9
  X->-3 X+3
  
  but if you try to use -3 for X it won't graph, this is partialy what limits are for (actually they are used to find tangent lines to a function but I'm not gonna explain ther here unless someone wants me to)
• BarrenSoul at 2005-03-06 05:54
  *sigh* forgot to sign in but that guest with the graph was me, I just wanted to say that png was made with the new pngout ;) (lol 0% original size >:) )