Why It Matters: Set Theory and Logic
Why understand set theory and logic applications?


- It takes three in a row to win the game.
- I cannot make three in a row no matter where I play on this turn.
- If it were my opponent’s turn, then she could make three in a row by putting an O in the upper left corner.
- If I don’t put my X in the upper left corner, then my opponent will have the opportunity to play there.
- Therefore, I must put an X in the upper left corner.

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- Why It Matters: Set Theory and Logic. Authored by: Lumen Learning. License: CC BY: Attribution.
- Tic Tac Toe game example. Authored by: Lumen Learning. License: CC BY: Attribution.
- Tic Tac Toe example play. Authored by: Lumen Learning. License: CC BY: Attribution.
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- Tic Tac Toe playground game. License: CC0: No Rights Reserved.