Proof trainer

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Interactive discrete math for CS students: topics, proof trainer, practice, and browser-native tools.

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Proof trainer

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Direct Proof

If n is odd, then n² is odd

Prove: If n is odd, then n² is odd.

Assume n is odd. for some integer k. = 2(2k² + 2k) + 1

Check your work to see the answer and the reasoning.