when it says, "that separates continuous and discontinuous inductance current". what exactly does that mean?

the book gives me formulas for continuous or discontinuous, but not both

thanks

 

It means continuous and discontinuous conduction mode.

 

allright maybe i didnt clearly state my question

my book gives me
Lm = (Vs*D)/(ΔiLm*f)
for continuous mode

and

Lm = (((1-D)^2*R)/(2f))*(N1/N2)^2
for discontinuous mode

which one is correct?