Nuprl Lemma : rv-Cauchy-Schwarz-equality

∀rv:InnerProductSpace. ∀a,b:Point(rv).  ((a ⋅ b^2 = (a^2 * b^2)) ⇒ b # 0 ⇒ (∃t:ℝ. a ≡ t*b))


Proof




Definitions occuring in Statement :  rv-ip: x ⋅ y,  inner-product-space: InnerProductSpace,  rv-mul: a*x,  rv-0: 0,  rnexp: x^k1,  req: x = y,  rmul: a * b,  real: ℝ,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  iff: P ⇐⇒ Q,  and: P ∧ Q,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  guard: {T},  uimplies: b supposing a,  prop: ℙ,  nat: ℕ,  le: A ≤ B,  less_than': less_than'(a;b),  not: ¬A,  false: False,  rneq: x ≠ y,  or: P ∨ Q,  uiff: uiff(P;Q),  rv-norm: ||x||,  rev_uimplies: rev_uimplies(P;Q),  rdiv: (x/y),  req_int_terms: t1 ≡ t2,  top: Top,  exists: ∃x:A. B[x]
Lemmas referenced :  rv-ip-positive,  Error :ss-sep_wf,  real-vector-space_subtype1,  inner-product-space_subtype,  subtype_rel_transitivity,  inner-product-space_wf,  real-vector-space_wf,  Error :separation-space_wf,  rv-0_wf,  req_wf,  rnexp_wf,  istype-void,  istype-le,  rv-ip_wf,  rmul_wf,  Error :ss-point_wf,  rv-norm-is-zero,  rv-sub_wf,  rv-mul_wf,  rdiv_wf,  rless_wf,  int-to-real_wf,  radd_wf,  rsub_wf,  rmul_preserves_req,  rminus_wf,  rinv_wf2,  itermSubtract_wf,  itermMultiply_wf,  itermAdd_wf,  itermVar_wf,  itermConstant_wf,  itermMinus_wf,  req_functionality,  rv-ip-sub-squared,  req_weakening,  radd_functionality,  req_transitivity,  rv-ip-mul,  rmul_functionality,  rv-ip-mul2,  rsub_functionality,  rmul-rinv3,  rmul-rinv,  req-iff-rsub-is-0,  real_polynomial_null,  istype-int,  real_term_value_sub_lemma,  real_term_value_mul_lemma,  real_term_value_add_lemma,  real_term_value_var_lemma,  real_term_value_const_lemma,  real_term_value_minus_lemma,  radd-preserves-req,  req_inversion,  rnexp2,  rsqrt_wf,  rv-ip-nonneg,  rleq_wf,  rleq_weakening_equal,  rsqrt0,  rsqrt_functionality,  Error :ss-eq_wf,  rv-sub-is-zero
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  productElimination,  independent_functionElimination,  hypothesis,  universeIsType,  isectElimination,  applyEquality,  instantiate,  independent_isectElimination,  sqequalRule,  dependent_set_memberEquality_alt,  natural_numberEquality,  independent_pairFormation,  voidElimination,  inhabitedIsType,  because_Cache,  inrFormation_alt,  closedConclusion,  minusEquality,  approximateComputation,  lambdaEquality_alt,  int_eqEquality,  isect_memberEquality_alt,  dependent_pairFormation_alt

Latex:
\mforall{}rv:InnerProductSpace.  \mforall{}a,b:Point(rv).    ((a  \mcdot{}  b\^{}2  =  (a\^{}2  *  b\^{}2))  {}\mRightarrow{}  b  \#  0  {}\mRightarrow{}  (\mexists{}t:\mBbbR{}.  a  \mequiv{}  t*b))



Date html generated: 2020_05_20-PM-01_11_53
Last ObjectModification: 2019_12_09-PM-11_41_12

Theory : inner!product!spaces


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