← Session 30 — ii′-5e squeeze capstone + 5f perimeter repair
thinking (6351 chars)
Two issues:
1. **Line 303**: `congr 1` — wait, I removed the congr 1 in my edit... line 303 is the `rw [h'', h.deriv]` area. "No goals to be solved" at 303 — the rw [h'', h.deriv] closed the goal?! The goal was `deriv (fun y => log y/y^2) x = (1−2log x)/x^3`; rw [h''] changes LHS to deriv (Real.log / fun y => y^2) x; rw [h.deriv] changes it to the value `(x⁻¹*x^2 − log x*(↑2*x^(2−1)))/(x^2)^2` — so the goal becomes `value = (1−2log x)/x^3` — NOT closed. Then line 303 `have hsimp ...` — hmm "No goals to be solved" at 303:12 — the rw [h'', h.deriv] might have CLOSED the goal?? No — the next error at 305 shows the goal `(x⁻¹*x^2 − ...)/(x^2)^2 = (1−2log x)/x^3` still open at the hsimp rw. So the "No goals" at 303 is a cascade artifact... Actually looking again: the two errors are: 303:8 "No goals to be solved" and 305:10 the rewrite failed. Line 303 is `rw [h'', h.deriv]`?? — if rw [h'', h.deriv] closed the goal (defeq between the value and (1−2log x)/x^3? no...). Hmm — actually "No goals" at 303 means the PREVIOUS tactic closed everything. Let me look at what's at line 303. From my edit: line ~297-306:
```
rw [h'', h.deriv]
have hsimp : (↑2 : ℝ) * x ^ (2 - 1) = 2 * x := by
rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]
push_cast
ring
rw [hsimp]
field_simp
ring
```
Line 303:8 = `rw [show (2:ℕ) − 1 = 1 from rfl, pow_one]` — "No goals to be solved": the hsimp's statement `(↑2:ℝ) * x^(2−1) = 2*x` — hmm "No goals" at the rw inside hsimp's proof — that means the show-statement `(↑2 : ℝ) * x ^ (2 - 1) = 2 * x` was ALREADY closed before the rw... no wait — "No goals to be solved" for the rw means the hsimp have's proof... Hmm — actually if hsimp's STATEMENT elaborated to `2 * x ^ (2-1) = 2 * x` (with (↑2:ℝ) evaluated to 2 by norm_num1 during elaboration?) then... the rw [show (2:ℕ)−1 = 1 from rfl] — the pattern (2:ℕ)−1 might not appear (already evaluated to 1)? Then rw fails with "did not find" — but the error is "No goals to be solved". Confusing cascade. And 305: rw [hsimp] failed — hsimp : 2 * x^(2−1) = 2*x but the goal has `↑2 * x^(2−1)` (with the Nat.cast ↑2) — hsimp's LHS is `2 * x^(2−1)` (OfNat 2) vs the goal's `↑2 * x^(2−1)` (Nat.cast 2) — MISMATCH: the deriv value has ↑2 (Nat cast) but my hsimp wrote (↑2 : ℝ) which displays as... I wrote `(↑2 : ℝ) * x ^ (2 - 1)` — and the error says hsimp : `2 * x ^ (2 - 1) = 2 * x` — so the elaborated hsimp has plain 2 not ↑2 (the (↑2:ℝ) got normalized by norm_num1 in the elaborator? or the ascription made it OfNat). And the goal has ↑2 (Nat.cast). So rw [hsimp] doesn't match.
Fix: make hsimp's LHS match the goal's `↑2 * x^(2−1)`: state hsimp as `((2:ℕ):ℝ) * x ^ (2 - 1) = 2 * x`:
```lean
have hsimp : ((2 : ℕ) : ℝ) * x ^ (2 - 1) = 2 * x := by
rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]
push_cast
ring
```
push_cast turns ((2:ℕ):ℝ) into (2:ℝ) ✓ then ring: 2*x = 2*x ✓.
Hmm — but the "No goals" at 303 — maybe after rw [h'', h.deriv] the elaborator... let me just also consider: maybe rw [h'', h.deriv] DIDN'T close; the "No goals" at 303 could be about the `have hsimp` block position... Actually the simplest: rewrite the hderiv block as:
```lean
have hderiv : deriv (fun y => Real.log y / y ^ 2) x
= (1 - 2 * Real.log x) / x ^ 3 := by
have h := (Real.hasDerivAt_log hx0).div (hasDerivAt_pow 2 x) (pow_ne_zero 2 hx0)
have h'' : (fun y => Real.log y / y ^ 2) = Real.log / (fun y => y ^ 2) := by
ext y
rw [Pi.div_apply]
rw [h'', h.deriv]
have hsimp : ((2 : ℕ) : ℝ) * x ^ (2 - 1) = 2 * x := by
rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]
push_cast
ring
rw [hsimp]
field_simp
ring
```
The remaining risk: after rw [h'', h.deriv], goal: `(x⁻¹ * x ^ 2 - Real.log x * (↑2 * x ^ (2 - 1))) / (x ^ 2) ^ 2 = (1 - 2 * Real.log x) / x ^ 3`. rw [hsimp] (matching ↑2): → `(x⁻¹ * x^2 − log x * (2*x))/(x^2)^2 = (1 − 2 log x)/x^3`. field_simp: clears denominators: LHS·(x²)²·x³ = RHS·... — produces a polynomial identity in x, log x, x⁻¹: (x⁻¹·x² − 2x·log x)·x³ =? (1−2 log x)·(x²)² ⟺ x·x³ − 2x⁴·log x·... hmm: (x⁻¹·x²)·x³ = x⁴·... let me verify the identity: LHS = (x − 2x·log x)/x⁴ = (1 − 2 log x)·x/x⁴ = (1−2log x)/x³ ✓ TRUE. field_simp + ring should manage with hx0 in context (field_simp uses hx0? field_simp needs the nonzero hyps: `field_simp [hx0]`). Let me write `field_simp [hx0]` — hmm field_simp picks up ne-hyps from context automatically? It looks for `x ≠ 0`-shaped hyps? Safer: field_simp [hx0]. Then ring.
Wait — actually, will `field_simp` produce something ring can close? The identity after clearing: (x⁻¹·x² − log x·(2x))·x³ = (1 − 2·log x)·(x²)²? Both sides polynomial in x and x⁻¹: LHS = x⁻¹·x²·x³ − 2x·log x·x³ = x⁴ − 2x⁴·log x·... x⁻¹·x²·x³ = x⁴? x⁻¹·x² = x; x·x³ = x⁴ ✓. RHS = x⁴ − 2x⁴ log x ✓ — ring closes (x⁻¹·x = 1 needed! ring treats x⁻¹ as an independent atom — x⁻¹·x² = x requires inv_mul_cancel! field_simp should eliminate x⁻¹ by clearing ALL denominators: the goal has x⁻¹, /(x²)², /x³ — field_simp multiplies through by x⁴·x³-ish: LHS·(x²)²·x³ and RHS... the x⁻¹ gets multiplied by x's — field_simp clears to: (x²·x³·...)·... it should work with hx0. If not, manually: rw [show x⁻¹ * x^2 = x from by field_simp [hx0]] first. Let me preemptively:
```lean
rw [hsimp]
have hx1 : x⁻¹ * x ^ 2 = x := by field_simp [hx0]
rw [hx1]
field_simp [hx0]
ring
```
hx1: x⁻¹·x² = x: field_simp [hx0]: multiplies: x² = x·x ✓ — hmm field_simp proves equalities with divisions; x⁻¹·x² = x — field_simp [hx0] might close it directly (it's a field identity) ✓ or `by rw [inv_mul_cancel_left₀ hx0]`? inv_mul_cancel_left₀ : a⁻¹ * a * b = b? hmm: x⁻¹·x² = x⁻¹·x·x = 1·x = x: rw [pow_two, ← mul_assoc, inv_mul_cancel₀ hx0, one_mul] — explicit:
```lean
have hx1 : x⁻¹ * x ^ 2 = x := by
rw [pow_two, ← mul_assoc, inv_mul_cancel₀ hx0, one_mul]
```
inv_mul_cancel₀ (h : a ≠ 0) : a⁻¹ * a = 1 ✓ (used earlier). Then after rw [hx1]: (x − log x·(2x))/(x²)² = (1−2log x)/x³: field_simp [hx0]; ring: LHS = (x − 2x log x)/x⁴; field_simp cross-multiplies by x⁴·x³: (x − 2x log x)·x³ = (1 − 2 log x)·x⁴: ring: x·x³ = x⁴ ✓ and 2x·log x·x³ = 2·x⁴·log x ✓ ring closes ✓.
2. **Line 305 area** — the same block. OK covered.
Let me rewrite the hderiv block with these.
Fixing the hsimp cast form and the field_simp chain in hderiv.
tool: Edit
input
{
"file_path": "D:\\Python\\Quantum\\research\\lean\\NguyenRH1\\NguyenRH1\\LiTightR.lean",
"old_string": " rw [h'', h.deriv]\n have hsimp : (\u21912 : \u211d) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : \u2115) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n rw [hsimp]\n field_simp\n ring\n rw [hderiv]\n exact div_nonpos_of_nonpos_of_nonneg (by linarith [hlogx]) (by positivity)",
"new_string": " rw [h'', h.deriv]\n have hsimp : ((2 : \u2115) : \u211d) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : \u2115) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n rw [hsimp]\n have hx1 : x\u207b\u00b9 * x ^ 2 = x := by\n rw [pow_two, \u2190 mul_assoc, inv_mul_cancel\u2080 hx0, one_mul]\n rw [hx1]\n field_simp [hx0]\n ring\n rw [hderiv]\n exact div_nonpos_of_nonpos_of_nonneg (by linarith [hlogx]) (by positivity)"
}
raw content_json (database row)
[{"type":"thinking","thinking":"Two issues:\n\n1. **Line 303**: `congr 1` — wait, I removed the congr 1 in my edit... line 303 is the `rw [h'', h.deriv]` area. \"No goals to be solved\" at 303 — the rw [h'', h.deriv] closed the goal?! The goal was `deriv (fun y => log y/y^2) x = (1−2log x)/x^3`; rw [h''] changes LHS to deriv (Real.log / fun y => y^2) x; rw [h.deriv] changes it to the value `(x⁻¹*x^2 − log x*(↑2*x^(2−1)))/(x^2)^2` — so the goal becomes `value = (1−2log x)/x^3` — NOT closed. Then line 303 `have hsimp ...` — hmm \"No goals to be solved\" at 303:12 — the rw [h'', h.deriv] might have CLOSED the goal?? No — the next error at 305 shows the goal `(x⁻¹*x^2 − ...)/(x^2)^2 = (1−2log x)/x^3` still open at the hsimp rw. So the \"No goals\" at 303 is a cascade artifact... Actually looking again: the two errors are: 303:8 \"No goals to be solved\" and 305:10 the rewrite failed. Line 303 is `rw [h'', h.deriv]`?? — if rw [h'', h.deriv] closed the goal (defeq between the value and (1−2log x)/x^3? no...). Hmm — actually \"No goals\" at 303 means the PREVIOUS tactic closed everything. Let me look at what's at line 303. From my edit: line ~297-306:\n```\n rw [h'', h.deriv]\n have hsimp : (↑2 : ℝ) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n rw [hsimp]\n field_simp\n ring\n```\nLine 303:8 = `rw [show (2:ℕ) − 1 = 1 from rfl, pow_one]` — \"No goals to be solved\": the hsimp's statement `(↑2:ℝ) * x^(2−1) = 2*x` — hmm \"No goals\" at the rw inside hsimp's proof — that means the show-statement `(↑2 : ℝ) * x ^ (2 - 1) = 2 * x` was ALREADY closed before the rw... no wait — \"No goals to be solved\" for the rw means the hsimp have's proof... Hmm — actually if hsimp's STATEMENT elaborated to `2 * x ^ (2-1) = 2 * x` (with (↑2:ℝ) evaluated to 2 by norm_num1 during elaboration?) then... the rw [show (2:ℕ)−1 = 1 from rfl] — the pattern (2:ℕ)−1 might not appear (already evaluated to 1)? Then rw fails with \"did not find\" — but the error is \"No goals to be solved\". Confusing cascade. And 305: rw [hsimp] failed — hsimp : 2 * x^(2−1) = 2*x but the goal has `↑2 * x^(2−1)` (with the Nat.cast ↑2) — hsimp's LHS is `2 * x^(2−1)` (OfNat 2) vs the goal's `↑2 * x^(2−1)` (Nat.cast 2) — MISMATCH: the deriv value has ↑2 (Nat cast) but my hsimp wrote (↑2 : ℝ) which displays as... I wrote `(↑2 : ℝ) * x ^ (2 - 1)` — and the error says hsimp : `2 * x ^ (2 - 1) = 2 * x` — so the elaborated hsimp has plain 2 not ↑2 (the (↑2:ℝ) got normalized by norm_num1 in the elaborator? or the ascription made it OfNat). And the goal has ↑2 (Nat.cast). So rw [hsimp] doesn't match.\n\nFix: make hsimp's LHS match the goal's `↑2 * x^(2−1)`: state hsimp as `((2:ℕ):ℝ) * x ^ (2 - 1) = 2 * x`:\n```lean\n have hsimp : ((2 : ℕ) : ℝ) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n```\npush_cast turns ((2:ℕ):ℝ) into (2:ℝ) ✓ then ring: 2*x = 2*x ✓.\n\nHmm — but the \"No goals\" at 303 — maybe after rw [h'', h.deriv] the elaborator... let me just also consider: maybe rw [h'', h.deriv] DIDN'T close; the \"No goals\" at 303 could be about the `have hsimp` block position... Actually the simplest: rewrite the hderiv block as:\n```lean\n have hderiv : deriv (fun y => Real.log y / y ^ 2) x\n = (1 - 2 * Real.log x) / x ^ 3 := by\n have h := (Real.hasDerivAt_log hx0).div (hasDerivAt_pow 2 x) (pow_ne_zero 2 hx0)\n have h'' : (fun y => Real.log y / y ^ 2) = Real.log / (fun y => y ^ 2) := by\n ext y\n rw [Pi.div_apply]\n rw [h'', h.deriv]\n have hsimp : ((2 : ℕ) : ℝ) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n rw [hsimp]\n field_simp\n ring\n```\nThe remaining risk: after rw [h'', h.deriv], goal: `(x⁻¹ * x ^ 2 - Real.log x * (↑2 * x ^ (2 - 1))) / (x ^ 2) ^ 2 = (1 - 2 * Real.log x) / x ^ 3`. rw [hsimp] (matching ↑2): → `(x⁻¹ * x^2 − log x * (2*x))/(x^2)^2 = (1 − 2 log x)/x^3`. field_simp: clears denominators: LHS·(x²)²·x³ = RHS·... — produces a polynomial identity in x, log x, x⁻¹: (x⁻¹·x² − 2x·log x)·x³ =? (1−2 log x)·(x²)² ⟺ x·x³ − 2x⁴·log x·... hmm: (x⁻¹·x²)·x³ = x⁴·... let me verify the identity: LHS = (x − 2x·log x)/x⁴ = (1 − 2 log x)·x/x⁴ = (1−2log x)/x³ ✓ TRUE. field_simp + ring should manage with hx0 in context (field_simp uses hx0? field_simp needs the nonzero hyps: `field_simp [hx0]`). Let me write `field_simp [hx0]` — hmm field_simp picks up ne-hyps from context automatically? It looks for `x ≠ 0`-shaped hyps? Safer: field_simp [hx0]. Then ring.\n\nWait — actually, will `field_simp` produce something ring can close? The identity after clearing: (x⁻¹·x² − log x·(2x))·x³ = (1 − 2·log x)·(x²)²? Both sides polynomial in x and x⁻¹: LHS = x⁻¹·x²·x³ − 2x·log x·x³ = x⁴ − 2x⁴·log x·... x⁻¹·x²·x³ = x⁴? x⁻¹·x² = x; x·x³ = x⁴ ✓. RHS = x⁴ − 2x⁴ log x ✓ — ring closes (x⁻¹·x = 1 needed! ring treats x⁻¹ as an independent atom — x⁻¹·x² = x requires inv_mul_cancel! field_simp should eliminate x⁻¹ by clearing ALL denominators: the goal has x⁻¹, /(x²)², /x³ — field_simp multiplies through by x⁴·x³-ish: LHS·(x²)²·x³ and RHS... the x⁻¹ gets multiplied by x's — field_simp clears to: (x²·x³·...)·... it should work with hx0. If not, manually: rw [show x⁻¹ * x^2 = x from by field_simp [hx0]] first. Let me preemptively:\n```lean\n rw [hsimp]\n have hx1 : x⁻¹ * x ^ 2 = x := by field_simp [hx0]\n rw [hx1]\n field_simp [hx0]\n ring\n```\nhx1: x⁻¹·x² = x: field_simp [hx0]: multiplies: x² = x·x ✓ — hmm field_simp proves equalities with divisions; x⁻¹·x² = x — field_simp [hx0] might close it directly (it's a field identity) ✓ or `by rw [inv_mul_cancel_left₀ hx0]`? inv_mul_cancel_left₀ : a⁻¹ * a * b = b? hmm: x⁻¹·x² = x⁻¹·x·x = 1·x = x: rw [pow_two, ← mul_assoc, inv_mul_cancel₀ hx0, one_mul] — explicit:\n```lean\n have hx1 : x⁻¹ * x ^ 2 = x := by\n rw [pow_two, ← mul_assoc, inv_mul_cancel₀ hx0, one_mul]\n```\ninv_mul_cancel₀ (h : a ≠ 0) : a⁻¹ * a = 1 ✓ (used earlier). Then after rw [hx1]: (x − log x·(2x))/(x²)² = (1−2log x)/x³: field_simp [hx0]; ring: LHS = (x − 2x log x)/x⁴; field_simp cross-multiplies by x⁴·x³: (x − 2x log x)·x³ = (1 − 2 log x)·x⁴: ring: x·x³ = x⁴ ✓ and 2x·log x·x³ = 2·x⁴·log x ✓ ring closes ✓.\n\n2. **Line 305 area** — the same block. OK covered.\n\nLet me rewrite the hderiv block with these.","signature":""},{"type":"text","text":"Fixing the hsimp cast form and the field_simp chain in hderiv."},{"type":"tool_use","id":"Edit_199","name":"Edit","input":{"file_path":"D:\\Python\\Quantum\\research\\lean\\NguyenRH1\\NguyenRH1\\LiTightR.lean","old_string":" rw [h'', h.deriv]\n have hsimp : (↑2 : ℝ) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n rw [hsimp]\n field_simp\n ring\n rw [hderiv]\n exact div_nonpos_of_nonpos_of_nonneg (by linarith [hlogx]) (by positivity)","new_string":" rw [h'', h.deriv]\n have hsimp : ((2 : ℕ) : ℝ) * x ^ (2 - 1) = 2 * x := by\n rw [show (2 : ℕ) - 1 = 1 from rfl, pow_one]\n push_cast\n ring\n rw [hsimp]\n have hx1 : x⁻¹ * x ^ 2 = x := by\n rw [pow_two, ← mul_assoc, inv_mul_cancel₀ hx0, one_mul]\n rw [hx1]\n field_simp [hx0]\n ring\n rw [hderiv]\n exact div_nonpos_of_nonpos_of_nonneg (by linarith [hlogx]) (by positivity)"},"extra_content":null}]