Question: Maple index help

Hi, i am new to Maple. I was trying to solve some problem and came up with the following difficulty:

When i give input

ai=(1+ki)/(1-ki);

 

and then do a_1 it gives the proper output as 

 

(1+k1)/(1-k1);

 

But whenever i try to do

ai,j=(ki-kj)2

it just gives back a1,2

A lot of work is stuck on this feature. Please help. Thank you

Please Wait...