MathGroup Archive 2009

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: binomial expansion of quantity raised to power of 1/2

  • To: mathgroup at smc.vnet.net
  • Subject: [mg101647] Re: [mg101598] binomial expansion of quantity raised to power of 1/2
  • From: "David Park" <djmpark at comcast.net>
  • Date: Sun, 12 Jul 2009 05:51:25 -0400 (EDT)
  • References: <32533955.1247283323674.JavaMail.root@n11>

Use a series expansion and specify that s is greater than zero. A series
expansion can be obtained either by using the Series command or simply by
adding an O[h]^n term to the expression.

Sqrt[-h^2 + s^2] + O[h]^5
Simplify[%, s > 0]                   giving

Sqrt[s^2]-(Sqrt[s^2] h^2)/(2 s^2)-(Sqrt[s^2] h^4)/(8 s^4)+O[h]^5
s-h^2/(2 s)-h^4/(8 s^3)+O[h]^5


David Park
djmpark at comcast.net
http://home.comcast.net/~djmpark/  


From: Roddye Davis [mailto:roddye at ca.rr.com] 

I saw in an engineering survey book a binomial expansion of (s^2 -
h^2)^(1/2) = s - (h^2/2s) - (h^4/(8(s^3)))....

How was this result achieved???????  Thanks.




  • Prev by Date: Re: binomial expansion of quantity raised to power of
  • Next by Date: Re: Re: Shortcut for Power
  • Previous by thread: Re: binomial expansion of quantity raised to power of 1/2
  • Next by thread: Derivative of a sum.