a) Use the predicate symbols: A(x), N(x), G(x), C(x) to write the above statements as a wff argument.
b) Using predicate logic, prove that the argument is valid.
2) Complete the following exhaustive proof of:
If a positive integer x is less than 10, then x2 < 200.
List positive integers x < 10 | List corresponding x2 | Is x2 < 200? |
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"If x is an odd integer and y is an even integer, then x + y is odd."
4) Use proof by contraposition to show:
"If x2 is even, then x is even."
5) Use proof by contradiction to show:
"If x2 is even, then x is even."