 Hello and welcome to the session. In this session, we are going to discuss symbolic notation of statements and negation of statements. Before we start, we shall know what a statement means. A statement is a sentence which is either true or false. It is also called a proposition. Now consider the following sentences. Washington DC is the capital of United States. What are you doing? What a beautiful painting. Let us see the first sentence. We will determine whether it is a statement or not. Now the first statement is Washington DC is the capital of United States. Now this is a statement because it is true that the capital of United States is Washington DC. So we write the sentence Washington DC is the capital of United States is a statement since it can be true or false and it happens to be true. Now let us see the second sentence. What are you doing? This sentence is not a statement. This is a question. Questions are not considered as statements. So we write the sentence what are you doing is not a statement. Now the third sentence is what a beautiful painting. This is also not a statement. If we carefully look at this sentence it is a comment or an opinion of a person. This opinion will differ from person to person. So we write the sentence what a beautiful painting is not a statement as it is a comment. Comments are not definitely true or false. So from these three examples we summarize statements are either true or false. Questions are not statements. Opinions and comments are also not statements. Now we come to the notation of a statement or we can say a proposition. We denote a statement by small letters p, q and r. For example the statement earth is round will be represented as p colon earth is round. Now let us discuss the truth value. The truth value of a statement is given by whether a statement is true or false. If a statement is true the truth value is t and if a statement is false the truth value is f. For example the statement p earth is round is true so its truth value will be t. Now let us discuss negation of a statement. Negation of a statement p is not p. So a statement and its negation have opposite truth values opposite meaning. Negation of a statement is symbolized by this and is read as not p. For example the statement p earth is round. Negation of p will be written as not p the earth is not round. So it has an opposite meaning to the statement p. Truth value of p is t. Now let us find the truth value of negation of p. Negation of p is the earth is not round. It is a false statement so its truth value is f. So here we can see that the truth value of negation p is false which is opposite to the truth value of p which is true. Thus in order to write the negation of a statement we write the given statement using not. So if statement p is true then negation p is false and if statement p is false then negation p is true. This completes our session. Hope you enjoyed the session.