Transforming NFA into DFA In the examples I was given I have the following NFA diagram:


Then it gives the conversion process

Could someone explain to me the process of obtaining the second column:

{1,2,4} = a{1, 2, 3, 4}, b{1, 4, 5}
This is the standard procedure for converting NFAs to DFAs. The first row should be read as "If you know you're in one of the states $0$, $1$ and $4$ and you read an $a$, you'll have to be in one of the states $1$, $2$ and $4$; if you read a $b$, you'll have to be in one of $1$, $4$ and $5$." The other rows are similar.