Nuprl Lemma : rneq-radd

∀x,y,a,b:ℝ.  (x + y ≠ a + b ⇒ (x ≠ a ∨ y ≠ b))


Proof




Definitions occuring in Statement :  rneq: x ≠ y,  radd: a + b,  real: ℝ,  all: ∀x:A. B[x],  implies: P ⇒ Q,  or: P ∨ Q
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  prop: ℙ,  uall: ∀[x:A]. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  so_lambda: λ2x.t[x],  or: P ∨ Q,  so_apply: x[s],  uimplies: b supposing a,  rge: x ≥ y,  guard: {T},  uiff: uiff(P;Q),  req_int_terms: t1 ≡ t2,  false: False,  not: ¬A,  top: Top
Lemmas referenced :  rless_wf,  int-to-real_wf,  rabs_wf,  rsub_wf,  radd_wf,  real_wf,  rneq-iff-rabs,  rneq_wf,  all_wf,  or_wf,  radd-positive-implies,  rless_functionality_wrt_implies,  rleq_weakening_equal,  r-triangle-inequality,  rminus_wf,  itermSubtract_wf,  itermAdd_wf,  itermVar_wf,  itermMinus_wf,  req-iff-rsub-is-0,  rless_functionality,  req_weakening,  rabs_functionality,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_add_lemma,  real_term_value_var_lemma,  real_term_value_minus_lemma,  real_term_value_const_lemma
Rules used in proof :  cut,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  natural_numberEquality,  hypothesis,  hypothesisEquality,  addLevel,  allFunctionality,  impliesFunctionality,  dependent_functionElimination,  productElimination,  independent_functionElimination,  orFunctionality,  sqequalRule,  lambdaEquality,  because_Cache,  functionEquality,  independent_isectElimination,  approximateComputation,  int_eqEquality,  intEquality,  isect_memberEquality,  voidElimination,  voidEquality

Latex:
\mforall{}x,y,a,b:\mBbbR{}.    (x  +  y  \mneq{}  a  +  b  {}\mRightarrow{}  (x  \mneq{}  a  \mvee{}  y  \mneq{}  b))



Date html generated: 2017_10_03-AM-08_46_47
Last ObjectModification: 2017_06_21-PM-03_20_06

Theory : reals


Home Index