Theorems / novel_alg_06

Authored

Algebra · medium

Statement, exactly as the model and Lean see it
theorem lg_target (x : ℝ) (h : x ^ 2 - 5 * x + 6 = 0) : x = 2 ∨ x = 3 := by
Source
Written for LeanGraph, reference proof certified
Premises used by the reference proof
66

Traces

Each configuration's full record: what was retrieved, what the model wrote, what Lean said back.

Verified0 model calls · 14 Lean checks · $0.00000

Attempts

  1. attempt 1Wrong tactic
    Proof
    rfl
    What Lean printed (this is all the model sees on repair)
    4:2: error: Tactic `rfl` failed: The left-hand side
      x = 2
    is not definitionally equal to the right-hand side
      x = 3
    
    x : ℝ
    h : x ^ 2 - 5 * x + 6 = 0
    ⊢ x = 2 ∨ x = 3
  2. attempt 2Other
    Proof
    decide
    What Lean printed (this is all the model sees on repair)
    4:2: error: Expected type must not contain free variables
      x = 2 ∨ x = 3
    
    Hint: Use the `+revert` option to automatically clean up and revert free variables
  3. attempt 3Valid but mathematically wrong
    Proof
    norm_num
    What Lean printed (this is all the model sees on repair)
    3:73: error: unsolved goals
    x : ℝ
    h : x ^ 2 - 5 * x + 6 = 0
    ⊢ x = 2 ∨ x = 3
  4. attempt 4Wrong tactic
    Proof
    simp
    What Lean printed (this is all the model sees on repair)
    4:2: error: `simp` made no progress
  5. attempt 5Wrong tactic
    Proof
    ring
    What Lean printed (this is all the model sees on repair)
    4:2: info: Try this:
      [apply] ring_nf
      
      The `ring` tactic failed to close the goal. Use `ring_nf` to obtain a normal form.
        
      Note that `ring` works primarily in *commutative* rings. If you have a noncommutative ring, abelian group or module, consider using `noncomm_ring`, `abel` or `module` instead.
    3:73: error: unsolved goals
    x : ℝ
    h : x ^ 2 - 5 * x + 6 = 0
    ⊢ x = 2 ∨ x = 3
  6. attempt 6Wrong tactic
    Proof
    linarith
    What Lean printed (this is all the model sees on repair)
    4:2: error: linarith failed to find a contradiction
    x : ℝ
    h : x ^ 2 - 5 * x + 6 = 0
    ⊢ False
    failed
  7. attempt 7Wrong tactic
    Proof
    nlinarith
    What Lean printed (this is all the model sees on repair)
    4:2: error: linarith failed to find a contradiction
    x : ℝ
    h : x ^ 2 - 5 * x + 6 = 0
    ⊢ False
    failed
  8. attempt 8Wrong tactic
    Proof
    positivity
    What Lean printed (this is all the model sees on repair)
    4:2: error: not a positivity goal
  9. attempt 9Wrong tactic
    Proof
    omega
    What Lean printed (this is all the model sees on repair)
    4:2: error: omega could not prove the goal:
    No usable constraints found. You may need to unfold definitions so `omega` can see linear arithmetic facts about `Nat` and `Int`, which may also involve multiplication, division, and modular remainder by constants.
  10. attempt 10Wrong tactic
    Proof
    field_simp
    What Lean printed (this is all the model sees on repair)
    4:2: error: `field_simp` made no progress on the goal
  11. attempt 11Wrong tactic
    Proof
    tauto
    What Lean printed (this is all the model sees on repair)
    4:2: error: Tactic `tauto` failed
    
    x : ℝ
    h : x ^ 2 - 5 * x + 6 = 0
    ⊢ x = 2 ∨ x = 3
  12. attempt 12Wrong tactic
    Proof
    simp_all
    What Lean printed (this is all the model sees on repair)
    4:2: error: simp_all made no progress
  13. attempt 13Wrong tactic
    Proof
    aesop
    What Lean printed (this is all the model sees on repair)
    4:2: error: Tactic `aesop` failed, made no progress
    Initial goal:
      x : ℝ
      h : x ^ 2 - 5 * x + 6 = 0
      ⊢ x = 2 ∨ x = 3
  14. attempt 14Verified
    Proof
    grind

Verified proof

theorem lg_target (x : ℝ) (h : x ^ 2 - 5 * x + 6 = 0) : x = 2 ∨ x = 3 := by
  grind

Axioms used: propext, Classical.choice, Quot.sound

Reference proof

The proof we wrote and certified before any model ran.

have h' : (x - 2) * (x - 3) = 0 := by ring_nf; linarith
rcases mul_eq_zero.mp h' with h1 | h1
· left; linarith
· right; linarith