Nuprl Lemma : quadratic-1-2-equal-implies

∀[a,b,c:ℝ].
  ((b * b) = (r(4) * a * c)) supposing 
     ((quadratic1(a;b;c) = quadratic2(a;b;c)) and 
     (r0 ≤ ((b * b) - r(4) * a * c)) and 
     a ≠ r0)


Proof




Definitions occuring in Statement :  quadratic2: quadratic2(a;b;c),  quadratic1: quadratic1(a;b;c),  rneq: x ≠ y,  rleq: x ≤ y,  rsub: x - y,  req: x = y,  rmul: a * b,  int-to-real: r(n),  real: ℝ,  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  natural_number: $n
Definitions unfolded in proof :  rev_uimplies: rev_uimplies(P;Q),  top: Top,  not: ¬A,  false: False,  req_int_terms: t1 ≡ t2,  uiff: uiff(P;Q),  subtype_rel: A ⊆r B,  quadratic1: quadratic1(a;b;c),  quadratic2: quadratic2(a;b;c),  guard: {T},  prop: ℙ,  true: True,  less_than': less_than'(a;b),  squash: ↓T,  less_than: a < b,  rev_implies: P ⇐ Q,  and: P ∧ Q,  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  all: ∀x:A. B[x],  or: P ∨ Q,  rneq: x ≠ y,  uimplies: b supposing a,  member: t ∈ T,  uall: ∀[x:A]. B[x]
Lemmas referenced :  rsqrt-is-zero,  radd-rminus,  real_term_value_minus_lemma,  real_term_value_add_lemma,  itermMinus_wf,  itermAdd_wf,  radd-rminus-assoc,  radd-preserves-req,  req_functionality,  rmul_preserves_req,  fractions-req,  real_term_value_var_lemma,  real_term_value_mul_lemma,  real_term_value_const_lemma,  real_term_value_sub_lemma,  real_polynomial_null,  req-iff-rsub-is-0,  itermVar_wf,  itermMultiply_wf,  itermConstant_wf,  itermSubtract_wf,  quadratic2_wf,  quadratic1_wf,  req_witness,  req-implies-req,  equal_wf,  rneq_wf,  real_wf,  rleq_wf,  rsqrt_wf,  rminus_wf,  radd_wf,  rdiv_wf,  req_wf,  rsub_wf,  rless_wf,  rmul-zero-both,  rmul_comm,  rmul_wf,  rless_functionality,  rless-int,  int-to-real_wf,  rmul_preserves_rless
Rules used in proof :  voidEquality,  voidElimination,  intEquality,  int_eqEquality,  approximateComputation,  isect_memberEquality,  equalitySymmetry,  equalityTransitivity,  productEquality,  setEquality,  rename,  setElimination,  lambdaEquality,  applyEquality,  dependent_set_memberEquality,  lambdaFormation,  inrFormation,  because_Cache,  independent_isectElimination,  baseClosed,  imageMemberEquality,  independent_pairFormation,  sqequalRule,  productElimination,  independent_functionElimination,  hypothesis,  natural_numberEquality,  isectElimination,  hypothesisEquality,  dependent_functionElimination,  extract_by_obid,  inlFormation,  thin,  unionElimination,  sqequalHypSubstitution,  cut,  introduction,  isect_memberFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}[a,b,c:\mBbbR{}].
    ((b  *  b)  =  (r(4)  *  a  *  c))  supposing 
          ((quadratic1(a;b;c)  =  quadratic2(a;b;c))  and 
          (r0  \mleq{}  ((b  *  b)  -  r(4)  *  a  *  c))  and 
          a  \mneq{}  r0)



Date html generated: 2018_05_22-PM-02_24_23
Last ObjectModification: 2018_05_21-AM-00_47_04

Theory : reals


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