It means that the output voltage should not vary more than 0.1% for the change in the supply voltage or the given load current step respectively for line and load regulation.
Jitendra Dhasmana.
write indeuctor current when switch is on (state 1)and off (state 2)and consider that current of inductor at last in state 1 is eqaul to the current of starting state 2.It will give you ΔI and ΔV =ΔQ/c
Added after 1 minutes:
write indeuctor current when switch is on (state 1)and off (state 2)and consider that current of inductor at last in state 1 is eqaul to the current of starting state 2 and f(frequncy)is (1/(T_on+T_off)).It will give you ΔI and ΔV =ΔQ/c
so I guess it is something like this, when you change the output load current, that is delta change in output voltage is what we term load regulation. Similary if we change the input and delta change in output voltage gives line regulation.