Knowing the expansion of a function, how can we find its expansion using the inverse of x? [migrated]

If we have a function like:

$ $ \text{f[x$ \_$ ]:=}\sum _{i=0}^{\infty } a_ix^i$ $

where we can find / know the $ a_i$ coefficients, but not really for which function it will converge.

How can we find $ f[x]$ but using the inverse of $ x$ instead? Something like this?

$ $ \text{f[x$ \_$ ]:=}\sum _{i=0}^{\infty } \frac{b_i}{x^i}$ $

The main problem is that the first form of $ f[x]$ does not converge properly for positive values greater than one, since it comes from a Taylor series.

How to make this div element the size of the img contained within it? [css] [migrated]

I am attempting to create a tooltip, to appear when hovering on an image within a table. However when I add the div to put a container for the tooltip, it adds extra spacing to my table, as seen in the first row (not applied to subsequent rows).

Why is the div 118 x 66 size as shown instead of the size of the image within it (59×59 )? It creates unnecessary spacing.

Oversized horitionzal dimension


CSS for tooltip

Tooltip in action

Unix permission other class [migrated]

Say I’m having the following configuration on a unix system:

usr : grp (User usr is of group grp). In addition I have group gurus.

And I’m running ls -l and get the following output:

-r--rw--w- 1 usr gurus  

Does usr have a write permission of this file? i.e does the ‘other’ class means “the whole world” or “not an owner nor a group member”?”


Configuring Azure Console for _external_ authentication/SSO/IdP? [migrated]

I’m looking for pointers on how to configure Azure “IAM” to trust an external IdP/Authentication server…. but finding my way around the docs for Azure which is… not easy. Help would be more than appreciated…

Some more context:

The challenge I have to solve should be “easy”: I need to use an 3rd party authentication/MFA solution to manage access to the Azure “cloud” console, to control which users access the console etc.

So my first idea is to configure the Azure console/IAM to use an external IdP for user access/SSO… Now, looking at the docs, I can see lots of info on how to use Azure AD to act as an IdP for other systems, but not so much on how to act as an SP for an external IDP. Also, I find all the different “flavours” of Azure AD that seem to be available somewhat confusing…

The closer I’ve been able to find is this:, but I’m not sure if that’s the approach to follow…

There are other articles like that seem to apply to using a SAML IDP for access to Office or other MS service — but not to the Azure “tenant” itself?

ANY tip more than appreciated 😉!!