Series expansion of ArcSin around 1

*To*: mathgroup at smc.vnet.net*Subject*: [mg21598] Series expansion of ArcSin around 1*From*: Jacek Pliszka <pliszka at fuw.edu.pl>*Date*: Sun, 16 Jan 2000 22:43:46 -0500 (EST)*Sender*: owner-wri-mathgroup at wolfram.com

Hi! I have the following problem. My x is close to 1 but sligthly smaller. I want to expand ArcSin[x] around 1 but this is what I get: In[53]:= Series[ArcSin[x],{x,1,4}] I 3/2 3 I 5/2 - (-1 + x) --- (-1 + x) Pi 6 80 Out[53]= -- - I Sqrt[2] Sqrt[-1 + x] + ------------- - --------------- + 2 Sqrt[2] Sqrt[2] 5 I 7/2 --- (-1 + x) 448 9/2 > --------------- + O[-1 + x] Sqrt[2] How to tell Mathematica that my x is real and smaller than 1 so it will not return all this complex numbers? Thanks for any help, Jacek