Optimizing K-Map Solution for Prime Implicants

[Ronaldo95163]

Homework Statement

-Posted in the diagram below-

Homework Equations

-None-

The Attempt at a Solution

I posted my solution below to obtain the prime implicants...however it's 3 implicants short of the suggested solution. What I don't understand is why are there so many redundant groups circled as prime implicants?

Shouldn't prime implicants be the largest possible group of 1s?
For example A'B is redundant as all its minterms are present in other groups...and this is the case for a few others...so I gave it a try on my own and what I got is shown in the picture.

It also didn't consider A'B and BD as essential implicants even though they have the don't care which is considered as 1 in this case that are not covered any other prime implicants

Also what do they mean by minimum cover?

Thanks

This is my solution:

 

[donpacino]

It looks like the problem is giving you many different possible ways to compelte the Kmap.

I think you need to figure out which ones are needed and which arent. In short, it looks like you took the right steps, now you simply need to answer the qeustion asked.

the minimum cover is the smallest number of arguments needed to complete the function.

hint: you can get rid of one of your arguments.