Compfiles/Imo2020P2.lean
1 declarations, 0 contain sorry, 0 declared as axioms
International Mathematical Olympiad 2020, Problem 2
The real numbers a, b, c, d are such that a ≥ b ≥ c ≥ d > 0 and a + b + c + d = 1.
Prove that (a + 2b + 3c + 4d) a^a b^b c^c d^d < 1.
Imported by 1 file
- problem
imo2020_p2line 29 sourcestandard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
Real,LT.lt,OfNat.ofNat,LE.le,Eq,HAdd.hAdd,HMul.hMul,Nat,HPow.hPowProof uses:
Real.geom_mean_le_arith_mean4_weighted,le_of_not_gt,Mathlib.Tactic.Linarith.lt_irrefl,Eq.mp,HSub.hSub,congrArg,Mathlib.Tactic.Ring.of_eq,Mathlib.Tactic.Ring.Common.add_congr,Nat.rawCast,Int.rawCast,inferInstance,Ring,Int.negOfNat,Mathlib.Tactic.Ring.Common.sub_congr,Mathlib.Tactic.Ring.cast_zero,Mathlib.Meta.NormNum.isNat_ofNat,Nat.cast_zero,Mathlib.Tactic.Ring.Common.atom_pf,rfl,Eq.mprand 102 more130 instances, coercions and auxiliary constants left out.
Tactic trace: 14 steps
Open to load the checked before-and-after goal states.