# Digital Electronics interview questions

11. What is DeMorgan’s Theory ?
DeMorgan’s first theorem states that two (or more) variables NOR´ed together is the same as the two variables inverted (Complement) and AND´ed, while the second theorem states that two (or more) variables NAND´ed together is the same as the two terms inverted (Complement) and OR´ed.

12. What is octal number system ?
The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7. Octal numerals can be made from binary numerals by grouping consecutive binary digits into groups of three (starting from the right). Octal is used when the number of bits in one word is a multiple of 3. It is also used as a shorthand for representing file permissions on UNIX systems and representation of UTF8 numbers.

13. What is a binary number system ?
A binary number is a number expressed in the base-2 numeral system or binary numeral system, which uses only two symbols: typically “0” and “1”. The base-2 numeral system is a positional notation with a radix of 2. Each digit is referred to as a bit. The system which has a base 2 is known as the binary system and it consists of only two digits 0 and 1.

14. Explain Minterm vs Maxterm ?
A minterm l is a product (AND) of all variables in the function, in direct or complemented form. A minterm has the property that it is equal to 1 on exactly one row of the truth table. A maxterm is a sum (OR) of all the variables in the function, in direct or complemented form.

15. What is duality theorem ?
The duality theorem states that,if the primal problem has an optimal solution, then so has the dual, and zP = zD.
If the primal problem is unbounded, then the dual is infeasible.
if the primal problem is infeasible, then the dual is either infeasible or unbounded.

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