differentiate

• Y_Shun

  3 Sep 07, 15:19

  x ln 2x - 0.5x with respect to x
• lpx88

  3 Sep 07, 15:24

  Lemme try..if wrong paiseh..
  
  Use product rule?
  
  xln2x - 1/2x
  =
  
  x(2/2x) + (1)ln2x - (1/2)
  
  =
  
  (1) + ln2x - (1/2)
  
  = ln2x +1/2
• Y_Shun

  3 Sep 07, 15:28

  :O ans correct.
  
  but differentiate ln2x is
  
  1/2x or
  
  (1/2x)(d/dx 2x) ????
• lpx88

  3 Sep 07, 15:52

  Originally posted by Y_Shun:

  :O ans correct.
  
  but differentiate ln2x is
  
  1/2x or
  
  (1/2x)(d/dx 2x) ????

  1/2x
  
  ln2x is only recognised as 1 single term.
• Y_Shun

  3 Sep 07, 16:02

  Originally posted by lpx88:

  1/2x
  
  ln2x is only recognised as 1 single term.

  no no...when differentiate its suppose to be
  
  1/[2x] then you are oso supposed to differentiate the 2x, and.... maybe wait for someone to confirm
  
  i asked another fren, his ans and mine correct...
• lpx88

  3 Sep 07, 16:11

  Originally posted by Y_Shun:

  no no...when differentiate its suppose to be
  
  1/[2x] then you are oso supposed to differentiate the 2x, and.... maybe wait for someone to confirm
  
  i asked another fren, his ans and mine correct...

  when u differentiate ln2x the final ans will alr be 1/2x. i think no need to differentiate further..is that what ur tryin to ask?
• Y_Shun

  3 Sep 07, 16:14

  Originally posted by lpx88:

  when u differentiate ln2x the final ans will alr be 1/2x. i think no need to differentiate further..is that what ur tryin to ask?

  err...no.
  
  can we get someone in to differentiate this qtn? LOL
• unclebutcher

  3 Sep 07, 16:16

  differentiate ln(ax) = 1/ax
  
  easy
• Y_Shun

  3 Sep 07, 16:25

  Originally posted by unclebutcher:

  differentiate ln(ax) = 1/ax
  
  easy

  then in what case do we need to differentiate ax again?
• Y_Shun

  3 Sep 07, 16:27

  what abt this: d/dx ln f( x ) = f ' ( x ) / f ( x )
• eagle

  3 Sep 07, 17:09

  Originally posted by unclebutcher:

  differentiate ln(ax) = 1/ax
  
  easy

  
  
  ln(ax) = ln a + ln x
  
  differentiatie ln (ax) is thus 1/x
  
  same as
  
  differentiate ln (ax) = 1/ax * a = 1/x
• eagle

  3 Sep 07, 17:10

  Originally posted by Y_Shun:

  :O ans correct.
  

  u sure?
• angelfairy

  3 Sep 07, 17:29

  Originally posted by lpx88:

  1/2x
  
  ln2x is only recognised as 1 single term.

  2/2x = 1/x -.-
• unclebutcher

  3 Sep 07, 17:44

  Originally posted by Y_Shun:

  then in what case do we need to differentiate ax again?

  sorry
  
  wrong
  
  d/dx ln(ax) = (1/ax)(a)
  
  
• unclebutcher

  3 Sep 07, 17:45

  Originally posted by Y_Shun:

  x ln 2x - 0.5x with respect to x

  x(1/x)+ln(2x) -0.5=
  
  ln(2x) + 0.5
• Y_Shun

  3 Sep 07, 20:03

  Originally posted by eagle:

  u sure?

  assessment book ans give ln2x
  
  but my ans is ln2x+0.5
  
  okay...so did anyone of you worked for that assessment book publisher before?
• lpx88

  3 Sep 07, 20:04

  Originally posted by Y_Shun:

  textbook ans give ln2x
  
  but my ans is ln2x+0.5
  
  okay...so did anyone of you worked for that assesment book publisher before?

  I tink the publisher committed the same careless mistake as me.... take ln2x as 1/2x thats why
• eagle

  3 Sep 07, 21:09

  Originally posted by Y_Shun:

  assessment book ans give ln2x
  
  but my ans is ln2x+0.5
  
  okay...so did anyone of you worked for that assessment book publisher before?

  Trust yourself more sometimes.