19 lines
504 B
Text
19 lines
504 B
Text
def f (x : Nat) := x
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theorem ex1 (h₁ : a = 0) (h₂ : a + b = 0) : f (b + c) = c := by
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simp_all
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simp [f]
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theorem ex2 (h₁ : a = 0) (h₂ : a + b = 0) : f (b + c) = c := by
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simp_all [f]
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theorem ex3 (h₁ : a = 0) (h₂ : a + b = 0) : f (b + c) = c := by
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simp_all only [f]
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rw [Nat.zero_add] at h₂
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simp [h₂]
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theorem ex4 (h₁ : a = f a) (h₂ : b + 0 = 0) : f b = 0 := by
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simp_all [-h₁]
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theorem ex5 (h₁ : a = f a) (h₂ : b + 0 = 0) : f (b + a) = a := by
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simp_all [-h₁, f]
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