Recently added robots.txt, validated, but pages still showing up

Validated in Google Sitemaps but pages still indexed

[blueheelers]

I recently added a robots.txt along with a Google Sitemap. I verified through Sitemaps that the particular pages were excluded.

The problem is that some of those pages were indexed before the robots.txt and they are still showing up in the search listings.

How do I get these pages to not show up in the listings? Will Google eventually drop them since they are now excluded?

Thanks

P.S.
The pages we were wanting to exclude were our support articles. The last thing I want is a customer seraching for our product and having the first page show help articles that refer to crashes and runtime errors :)

[Dijkgraaf]

See
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