You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
lean4game/server/testgame/TestGame/Levels/Proposition/L07_ContraNotEq.lean

31 lines
598 B
Plaintext

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

import TestGame.Metadata
import Std.Tactic.RCases
import Mathlib.Tactic.LeftRight
import TestGame.ToBePorted
Game "TestGame"
World "Proposition"
Level 8
Title "Widerspruch"
Introduction
"
Zweitens kann `contradiction` auch aus Annahmen der Form `a ≠ a` einen Widerspruch finden.
*Bemerkung:* Das Ungleichzeichen `≠` (`\\ne`) sollte immer als `¬(· = ·)` gelesen werden.
"
Statement
"Sei $n$ eine natürliche Zahl die ungleich sich selbst ist. Dann ist $n = 37$."
(n : ) (h : n ≠ n) : n = 37 := by
contradiction
Conclusion
"
"
NewTactics contradiction
DisabledTactics tauto