I have this expression: ACD+ABC+BD+ACD, where underlined letters are complements.
How can I realise this function using only:
a)NAND gate
b)NOR gate
I suppose that I should transform function above to get 2 new functions,one for realisation using only NAND gates, and second for realisation using only NOR gates.How can I do it?

 

I will use exclamation in front of signal to indicate that signal is inverted.

a)
NAND1 = inputs A, C, !D
NAND2 = inputs A, B, !C
NAND3 = inputs B, !D
NAND4 = A, !C, D
NAND5 = inputs are outputs from previous gates.

normally it is assumed that signals are available in direct and inverted form. if you need to create inverted signals for C and D, you can use additional pair of NANDs as inverters (just connect inputs of the NAND gate together).

b)
just use DeMorgan

NOR1 = inputs !A, !C, D
NOR2 = inputs !A, !B, C
etc.
NOR5 = inputs are from previous NOR gates.

just like with NAND, you can use NOR to make invertor by connecting inputs of the NOR gate together.

 

This thread has been moved to Homework Help section, where it seems more fitting.