Math Help - subscripts of subscripts

1. subscripts of subscripts

Can anyone help me with subscripts of subscripts - that is I want to type

f sub a sub i

I have tried f_a_i

but the a and the i ended up on the same level

I would be really grateful for help on this issue

Peter

2. Re: subscripts of subscripts

Originally Posted by Bernhard
Can anyone help me with subscripts of subscripts - that is I want to type

f sub a sub i

I have tried f_a_i

but the a and the i ended up on the same level

I would be really grateful for help on this issue

Peter
f_{a_i} gives:

$f_{a_i}$

CB