maclaurin's expansion

• striderz_o405

  13 Sep 07, 05:18

  how to expand ln (1-sin x) ?
  
• unclebutcher

  13 Sep 07, 14:38

  oops i wanted to quote but accidentally edited
• unclebutcher

  13 Sep 07, 14:39

  differentiate ln(1-sinx) until the number of terms u want it. very easy actually. pls post full qn if u want a full answer.
• ^tamago^

  13 Sep 07, 18:10

  use ln(1+u) = u - u^2/2 + u^3/3 + ...
  and
  put u = -sin x
  which expands to -x + x^3/3! - x^5+5!
  
  sub the 2nd expansion in to ln(1+u) and u should get
  -x -x^2/2 -x^3/6 -x^4/6 +x^5/9 +7x^6/360
• striderz_o405

  13 Sep 07, 20:41

  Originally posted by ^tamago^:

  use ln(1+u) = u - u^2/2 + u^3/3 + ...
  and
  put u = -sin x
  which expands to -x + x^3/3! - x^5+5!
  
  sub the 2nd expansion in to ln(1+u) and u should get
  -x -x^2/2 -x^3/6 -x^4/6 +x^5/9 +7x^6/360

  sorta get about the same this answer too. lol
  
  just wanna double check
  
  my exam ques btw
• ^tamago^

  13 Sep 07, 21:03

  Originally posted by striderz_o405:

  sorta get about the same this answer too. lol
  
  just wanna double check
  
  my exam ques btw

  ok. it's not tough, but it's a tedious one to do.