Nuprl Lemma : rabs-int-rmul-unit

[k:ℕ]. ∀[x:ℝ].  (|-1^k x| |x|)


Proof




Definitions occuring in Statement :  rabs: |x| int-rmul: k1 a req: y real: nat: uall: [x:A]. B[x] minus: -n natural_number: $n fastexp: i^n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T implies:  Q subtype_rel: A ⊆B nat: uimplies: supposing a uiff: uiff(P;Q) and: P ∧ Q rev_uimplies: rev_uimplies(P;Q) sq_type: SQType(T) rev_implies:  Q iff: ⇐⇒ Q guard: {T} prop: true: True less_than': less_than'(a;b) squash: T less_than: a < b all: x:A. B[x] so_apply: x[s] so_lambda: λ2x.t[x] nat_plus: + absval: |i|
Lemmas referenced :  req_witness rabs_wf int-rmul_wf fastexp_wf real_wf nat_wf absval_wf req_functionality rabs-int-rmul req_weakening absval_exp exp-fastexp iff_weakening_equal exp-one true_wf squash_wf equal_wf exp-positive-stronger int_subtype_base less_than_wf set_subtype_base nat_plus_wf subtype_base_sq int-rmul-one
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut extract_by_obid sqequalHypSubstitution isectElimination thin minusEquality natural_numberEquality hypothesisEquality hypothesis independent_functionElimination sqequalRule isect_memberEquality because_Cache applyEquality lambdaEquality setElimination rename independent_isectElimination productElimination universeEquality equalitySymmetry equalityTransitivity imageElimination baseClosed imageMemberEquality independent_pairFormation dependent_set_memberEquality dependent_functionElimination intEquality cumulativity instantiate

Latex:
\mforall{}[k:\mBbbN{}].  \mforall{}[x:\mBbbR{}].    (|-1\^{}k  *  x|  =  |x|)



Date html generated: 2017_10_03-AM-08_29_05
Last ObjectModification: 2017_07_28-AM-07_25_41

Theory : reals


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