Formal logic deals with true and false values instead of numbers. It was developed in the mid-19th century by George Bool and uses "AND" and "OR" operators instead of addition and multiplication. There are three main logic gates: the NOT gate inverts the input; the AND gate only outputs true if all inputs are true; the OR gate outputs true if any input is true.

3.  Formal logic is a branch of
mathematics that deals
with true and false values
instead of numbers.
• In the mid-19th century, George Bool
developed many Logic ideas.
• Boolean logic deals with equations where
the operators are “AND” or “OR” instead of
“add” and “multiply”.

4. Types of logic gates -:

5. • The NOT gate is an electronic circuit
that produces an inverted version of
the input at its output.
• It is also known as an inverter.
• If the input variable is A, the inverted
output is known as NOT A.
• This is also shown as A', or Ā with a
Bar over the top

6. This is for 1 I/ps…
A Q
0 1
1 0

7. 2)
 The AND gate is an electronic circuit that
gives a true output (1) only if all its inputs
are true. A dot (·) is used to show the AND
operation i.e. A·B. Note that the dot is
sometimes omitted i.e. AB…
 And is used for multiplication purpose (*)…

8. This is for 2 I/ps……
A B Y
0 0 0
0 1 0
1 0 0
1 1 1

9. 3) OR GATE -:

10. Truth table Symbol
This is for 2 I/ps…….
A B Y
0 0 0
0 1 1
1 0 1
1 1 1