Nuprl Lemma : r2-straightedge-compass

c,d,a:ℝ^2. ∀b:{b:ℝ^2| b ≠ a ∧ c_b_d} .
  ∃u:{u:ℝ^2| cu=cd ∧ a_b_u} 
   (∃v:ℝ^2 [(cv=cd ∧ v_b_u ∧ ((¬a_b_v) ∧ b_v_a) ∧ v_a_b))) ∧ (b ≠  (v ≠ u ∧ u ≠ b ∧ v ≠ b)))])


Proof




Definitions occuring in Statement :  rv-be: a_b_c real-vec-sep: a ≠ b rv-congruent: ab=cd real-vec: ^n all: x:A. B[x] sq_exists: x:A [B[x]] exists: x:A. B[x] not: ¬A implies:  Q and: P ∧ Q set: {x:A| B[x]}  natural_number: $n
Definitions unfolded in proof :  all: x:A. B[x] member: t ∈ T prop: uall: [x:A]. B[x] nat: le: A ≤ B and: P ∧ Q less_than': less_than'(a;b) false: False not: ¬A implies:  Q so_lambda: λ2x.t[x] so_apply: x[s] sq_stable: SqStable(P) squash: T exists: x:A. B[x] real-vec: ^n int_seg: {i..j-} subtype_rel: A ⊆B real-vec-dist: d(x;y) real-vec-norm: ||x|| real-vec-sub: Y nat_plus: + less_than: a < b true: True real: eq_int: (i =z j) ifthenelse: if then else fi  btrue: tt bfalse: ff uiff: uiff(P;Q) uimplies: supposing a rev_uimplies: rev_uimplies(P;Q) req_int_terms: t1 ≡ t2 top: Top iff: ⇐⇒ Q rev_implies:  Q cand: c∧ B real-vec-sep: a ≠ b rge: x ≥ y guard: {T} rv-congruent: ab=cd rv-be: a_b_c rv-between: a-b-c sq_exists: x:A [B[x]]
Lemmas referenced :  set_wf real-vec_wf false_wf le_wf real-vec-sep_wf rv-be_wf sq_stable__real-vec-sep real_wf ifthenelse_wf eq_int_wf radd_wf rabs_wf int-to-real_wf int_seg_wf req_wf real-vec-dist_wf exists_wf rleq_wf dot-product_wf real-vec-sub_wf rmul_wf real-regular rsub_wf less_than_wf regular-int-seq_wf itermSubtract_wf itermAdd_wf itermMultiply_wf itermVar_wf itermConstant_wf req-iff-rsub-is-0 req_functionality r2-dot-product req_weakening real_polynomial_null real_term_value_sub_lemma real_term_value_add_lemma real_term_value_mul_lemma real_term_value_var_lemma real_term_value_const_lemma rsqrt_wf dot-product-nonneg square-nonneg rsqrt-of-square radd-non-neg zero-rleq-rabs rleq-int rsqrt_functionality rv-extend real-vec-between_wf rless_wf rless_functionality trivial-rless-radd rless-int rless_functionality_wrt_implies rleq_weakening_equal radd_functionality_wrt_rleq sq_stable__rless real-vec-dist-between req_transitivity radd_functionality real-vec-dist-nonneg rabs-bounds radd-preserves-rless rminus_wf radd-rminus-both itermMinus_wf real_term_value_minus_lemma rv-be-symmetry not_wf rv-between_wf rless_transitivity2 real-vec-triangle-inequality rless_transitivity1 real-vec-dist-symmetry rless-implies-rless rv-line-circle-3-ext sq_stable__rv-be rv-be-inner-trans req_inversion rv-congruent_wf sq_exists_wf rv-pos-angle_wf rv-be-dist rv-pos-angle-shift rv-pos-angle-permute rv-pos-angle-not-be rv-pos-angle-symmetry not-rv-pos-angle-implies2 rv-T-iff rv-T_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin dependent_set_memberEquality natural_numberEquality sqequalRule independent_pairFormation hypothesis hypothesisEquality lambdaEquality productEquality because_Cache setElimination rename dependent_functionElimination productElimination independent_functionElimination imageMemberEquality baseClosed imageElimination dependent_pairFormation applyEquality setEquality independent_isectElimination approximateComputation int_eqEquality intEquality isect_memberEquality voidElimination voidEquality equalityTransitivity equalitySymmetry functionEquality impliesFunctionality promote_hyp

Latex:
\mforall{}c,d,a:\mBbbR{}\^{}2.  \mforall{}b:\{b:\mBbbR{}\^{}2|  b  \mneq{}  a  \mwedge{}  c\_b\_d\}  .
    \mexists{}u:\{u:\mBbbR{}\^{}2|  cu=cd  \mwedge{}  a\_b\_u\} 
      (\mexists{}v:\mBbbR{}\^{}2  [(cv=cd
                      \mwedge{}  v\_b\_u
                      \mwedge{}  (\mneg{}((\mneg{}a\_b\_v)  \mwedge{}  (\mneg{}b\_v\_a)  \mwedge{}  (\mneg{}v\_a\_b)))
                      \mwedge{}  (b  \mneq{}  d  {}\mRightarrow{}  (v  \mneq{}  u  \mwedge{}  u  \mneq{}  b  \mwedge{}  v  \mneq{}  b)))])



Date html generated: 2018_05_22-PM-02_36_58
Last ObjectModification: 2018_05_18-AM-09_46_36

Theory : reals


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