Lecture 1:

1). bsorption laws - good explanation + equivalence transforms.:
https://www.youtube.com/watch?v=eihhu72YdpQ


2). Logical Equivalence:
https://www.youtube.com/watch?v=oY8Xt5GvZ1g

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Lecture 2:

1). Canonical representation of Boolean Functions: 
CNF and DNF / Product of Sums an d Sum of Products:
https://www.youtube.com/watch?v=Gjsfx-o7nnQ

2). Negation Normal Forms:
https://www.youtube.com/watch?v=XMoGOOYa2Yw

3). Transformation to: DNF: 
https://www.youtube.com/watch?v=D7nyonAsIo8  1.58




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Lecture 3:

1). Logic: Direct correct proof:
https://www.youtube.com/watch?v=YFZzLQN5qOU

2). Logic: Proof by contradiction
https://www.youtube.com/watch?v=sRDwsfNDXak

3). Prove by contradiction - aritmetic mean greate than geometric one:
https://www.youtube.com/watch?v=cpongofEZ8I

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Two false proofs:

Let us prove that 2+2=5
https://www.youtube.com/watch?v=Cpug-FCZjhU

Let us prove that 3=0
https://www.youtube.com/watch?v=SGUZ-8u1OxM