how to integrate this?

• weiwei83

  4 Feb 07, 13:54

  integrate (1/(60+x)) with respect to x.
  
  Is the answer just ln(60+x) or you need to consider the 60?
• Diehard_89

  4 Feb 07, 13:55

  ln(60+x) + C
  
  no need to consider 60
• aku1b0d0

  4 Feb 07, 13:59

  lemme see..isit x=1/60?
• weiwei83

  4 Feb 07, 14:00

  Then what about
  
  exponential^(Integrate [3/(60-x)])=?
• omgukilledkenny

  4 Feb 07, 14:02

  erm, then what happens when...
  i differentiate ln(5x) = 1/x
  and differentiating ln(6x) is also = 1/x
  
  so when integrating 1/x how do i know if its ln(6x) +C or ln(5x) +C ?
• OO_OO_OO

  4 Feb 07, 14:02

  Originally posted by weiwei83:

  Then what about
  
  exponential^(Integrate [3/(60-x)])=?

  wha shit i forgot all my math already lol..
  i think its by parts or smt.
  equate that whole thing to y and make it ln.
• weiwei83

  4 Feb 07, 14:03

  Originally posted by OO_OO_OO:

  wha shit i forgot all my math already lol..
  i think its by parts or smt.
  equate that whole thing to y and make it ln.

  No i am talking about integrating factor here.
  e to the power of integrate something.
• OO_OO_OO

  4 Feb 07, 14:05

  oh differential equation...
  
  its e^-ln(60-x)
• weiwei83

  4 Feb 07, 14:06

  Originally posted by OO_OO_OO:

  oh differential equation...
  
  its e^-ln(60-x)

  how to reduce further. btw, my question got one number 3.
• omgukilledkenny

  4 Feb 07, 14:07

  Originally posted by weiwei83:

  Then what about
  
  exponential^(Integrate [3/(60-x)])=?

  erm..izzit (60-x)^3 ?
• weiwei83

  4 Feb 07, 14:08

  Originally posted by omgukilledkenny:

  erm..izzit (60-x)^3 ?

  should be (60-x)^-3...but dunno why my teacher say its not. Its [60/(60-x)]^3...
  
• kenshin_himura

  4 Feb 07, 14:10

  Originally posted by omgukilledkenny:

  erm, then what happens when...
  i differentiate ln(5x) = 1/x
  and differentiating ln(6x) is also = 1/x
  
  so when integrating 1/x how do i know if its ln(6x) +C or ln(5x) +C ?

  integrate 1/x = lnX
  
  but theres one thing i rmb! always dun complicate stuff!
• Chuichi Koshiramaru

  4 Feb 07, 14:21

  Wah, chim!
  *mental block*
  
• omgukilledkenny

  4 Feb 07, 14:23

  Originally posted by weiwei83:

  should be (60-x)^-3...but dunno why my teacher say its not. Its [60/(60-x)]^3...
  

  oops ya its (60-x)^-3
  
  ur teacher wrong bah =P