`Compfiles/Imo1960P2.lean`

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3 declarations, 0 contain sorry, 0 declared as axioms

International Mathematical Olympiad 1960, Problem 2

For what values of the variable $x$ does the following inequality hold:

\[\dfrac{4x^2}{(1 - \sqrt {2x + 1})^2} < 2x + 9 \ ?\]

Imports (2)

Imported by 1 file

Compfiles.lean

structure Imo1960Q2.IsGood The predicate says that x satisfies the inequality \[\dfrac{4x^2}{(1 - \sqrt {2x + 1})^2} < 2x + 9\] and belongs to the domain of the function on the left-hand side line 39 source
Source documentation
The predicate says that x satisfies the inequality
\[\dfrac{4x^2}{(1 - \sqrt {2x + 1})^2} < 2x + 9\]
and belongs to the domain of the function on the left-hand side.

standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Real
```
structure IsGood (x : ℝ) : Prop where
…
```
determine Imo1960Q2.SolutionSet line 47 source
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Set, Real
Proof uses: SDiff.sdiff, Set.Ico, HDiv.hDiv, Neg.neg, OfNat.ofNat, Singleton.singleton
16 instances, coercions and auxiliary constants left out.
problem Imo1960Q2.imo1960_p2 line 49 source
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses: Real, Iff, Imo1960Q2.IsGood, Membership.mem, Set, Imo1960Q2.SolutionSet
Proof uses: Eq, OfNat.ofNat, Ne, Or, eq_or_ne, of_eq_true, Eq.trans, False, True, congr, congrArg, And, LT.lt, HDiv.hDiv, HMul.hMul, Nat, HPow.hPow, HSub.hSub, Real.sqrt, HAdd.hAdd and 152 more
159 instances, coercions and auxiliary constants left out.

Tactic trace: 26 steps
Open to load the checked before-and-after goal states.