Nuprl Lemma : rsqrt-rmul
∀x:{x:ℝ| r0 ≤ x} . ∀[y:{x:ℝ| r0 ≤ x} ]. ((rsqrt(x) * rsqrt(y)) = rsqrt(x * y))
Proof
Definitions occuring in Statement : 
rsqrt: rsqrt(x), 
rleq: x ≤ y, 
req: x = y, 
rmul: a * b, 
int-to-real: r(n), 
real: ℝ, 
uall: ∀[x:A]. B[x], 
all: ∀x:A. B[x], 
set: {x:A| B[x]} , 
natural_number: $n
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
prop: ℙ, 
subtype_rel: A ⊆r B, 
and: P ∧ Q, 
uimplies: b supposing a, 
sq_stable: SqStable(P), 
implies: P ⇒ Q, 
squash: ↓T, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
itermConstant: "const", 
req_int_terms: t1 ≡ t2, 
false: False, 
not: ¬A, 
top: Top, 
uiff: uiff(P;Q), 
rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced : 
req_witness, 
rmul_wf, 
rsqrt_wf, 
rleq_wf, 
int-to-real_wf, 
real_wf, 
req_wf, 
rmul-nonneg-case1, 
sq_stable__rleq, 
set_wf, 
rsqrt-unique, 
rsqrt_nonneg, 
req_functionality, 
req_transitivity, 
real_term_polynomial, 
itermSubtract_wf, 
itermMultiply_wf, 
itermVar_wf, 
real_term_value_const_lemma, 
real_term_value_sub_lemma, 
real_term_value_mul_lemma, 
real_term_value_var_lemma, 
req-iff-rsub-is-0, 
rmul_functionality, 
req_weakening, 
rsqrt_squared, 
rmul-assoc
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
isect_memberFormation, 
introduction, 
cut, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
setElimination, 
rename, 
dependent_set_memberEquality, 
hypothesisEquality, 
hypothesis, 
natural_numberEquality, 
applyEquality, 
lambdaEquality, 
setEquality, 
productEquality, 
sqequalRule, 
because_Cache, 
independent_isectElimination, 
independent_pairFormation, 
independent_functionElimination, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
dependent_functionElimination, 
computeAll, 
int_eqEquality, 
intEquality, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
productElimination
Latex:
\mforall{}x:\{x:\mBbbR{}|  r0  \mleq{}  x\}  .  \mforall{}[y:\{x:\mBbbR{}|  r0  \mleq{}  x\}  ].  ((rsqrt(x)  *  rsqrt(y))  =  rsqrt(x  *  y))
 Date html generated: 
2017_10_03-AM-10_43_55
 Last ObjectModification: 
2017_07_28-AM-08_18_45
Theory : reals
Home
Index