# Why can't I get the expression for this karnaugh map using minterms?

I am getting ab + bc'd' + ab'c', But I keep failing, it doesn't work for my table.

Can someone explain to me what am I doing wrong? This is using minterms.

There is firstly a mistake, it is not $ab'c'$ but $ab'c$. And you also have to keep in mind that the table rolls in the edges (both left/right AND bottom/top), so that the two lower 1's can be grouped with the two upper 1's. The last term $ab'c$ can then be further reduced to $ac$. Finally you forgot one 1 alone, which is $a'b'c'd$.