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Not Another NAND!

Age 14 to 18
Challenge Level Yellow starYellow star
  • Problem
  • Getting Started
  • Student Solutions

 

The NAND gate is said to be universal. This means that the effect of any other logic gate can be replicated using just NAND gates.

Prove that this is indeed the case: replicate AND, OR, XOR, XNOR, NOR, NOT gates using just NAND gates.

Are any of the other types of gate universal? Prove it.


 

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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