Nuprl Lemma : rmul_preserves_rneq_iff
∀a,b,x:ℝ.  (x ≠ r0 ⇒ (a ≠ b ⇐⇒ x * a ≠ x * b))
Proof
Definitions occuring in Statement : 
rneq: x ≠ y, 
rmul: a * b, 
int-to-real: r(n), 
real: ℝ, 
all: ∀x:A. B[x], 
iff: P ⇐⇒ Q, 
implies: P ⇒ Q, 
natural_number: $n
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
member: t ∈ T, 
prop: ℙ, 
uall: ∀[x:A]. B[x], 
rev_implies: P ⇐ Q, 
rneq: x ≠ y, 
or: P ∨ Q, 
uimplies: b supposing a, 
uiff: uiff(P;Q), 
req_int_terms: t1 ≡ t2, 
false: False, 
not: ¬A, 
top: Top
Lemmas referenced : 
rneq_wf, 
rmul_wf, 
int-to-real_wf, 
real_wf, 
rmul_preserves_rneq, 
rmul_reverses_rless_iff, 
rless-implies-rless, 
rless_wf, 
rmul_preserves_rless, 
rsub_wf, 
itermSubtract_wf, 
itermMultiply_wf, 
itermVar_wf, 
req-iff-rsub-is-0, 
real_polynomial_null, 
real_term_value_sub_lemma, 
real_term_value_mul_lemma, 
real_term_value_var_lemma, 
real_term_value_const_lemma
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
independent_pairFormation, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
natural_numberEquality, 
dependent_functionElimination, 
independent_functionElimination, 
unionElimination, 
inrFormation, 
productElimination, 
independent_isectElimination, 
inlFormation, 
because_Cache, 
sqequalRule, 
approximateComputation, 
lambdaEquality, 
int_eqEquality, 
intEquality, 
isect_memberEquality, 
voidElimination, 
voidEquality
Latex:
\mforall{}a,b,x:\mBbbR{}.    (x  \mneq{}  r0  {}\mRightarrow{}  (a  \mneq{}  b  \mLeftarrow{}{}\mRightarrow{}  x  *  a  \mneq{}  x  *  b))
 Date html generated: 
2017_10_03-AM-08_35_16
 Last ObjectModification: 
2017_06_16-PM-00_46_33
Theory : reals
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