Nuprl Lemma : rsin-reduce2
∀[x:ℝ]. (rsin(x) = 2 * rsin((x)/2) * rcos((x)/2))
Proof
Definitions occuring in Statement :
rcos: rcos(x),
rsin: rsin(x),
int-rdiv: (a)/k1,
int-rmul: k1 * a,
req: x = y,
rmul: a * b,
real: ℝ,
uall: ∀[x:A]. B[x],
natural_number: $n
Definitions unfolded in proof :
uall: ∀[x:A]. B[x],
member: t ∈ T,
int_nzero: ℤ-o,
true: True,
nequal: a ≠ b ∈ T ,
not: ¬A,
implies: P ⇒ Q,
uimplies: b supposing a,
sq_type: SQType(T),
all: ∀x:A. B[x],
guard: {T},
false: False,
prop: ℙ,
uiff: uiff(P;Q),
and: P ∧ Q,
rev_uimplies: rev_uimplies(P;Q),
req_int_terms: t1 ≡ t2,
top: Top,
iff: P ⇐⇒ Q,
rneq: x ≠ y,
or: P ∨ Q,
rev_implies: P ⇐ Q,
less_than: a < b,
squash: ↓T,
less_than': less_than'(a;b),
decidable: Dec(P),
satisfiable_int_formula: satisfiable_int_formula(fmla),
exists: ∃x:A. B[x],
rdiv: (x/y)
Lemmas referenced :
req_witness,
rsin_wf,
int-rmul_wf,
rmul_wf,
int-rdiv_wf,
subtype_base_sq,
int_subtype_base,
istype-int,
nequal_wf,
rcos_wf,
real_wf,
radd_wf,
int-to-real_wf,
itermSubtract_wf,
itermAdd_wf,
itermMultiply_wf,
itermVar_wf,
itermConstant_wf,
req-iff-rsub-is-0,
req_wf,
rsin-radd,
req_functionality,
req_weakening,
int-rmul-req,
real_polynomial_null,
real_term_value_sub_lemma,
istype-void,
real_term_value_add_lemma,
real_term_value_mul_lemma,
real_term_value_var_lemma,
real_term_value_const_lemma,
iff_weakening_uiff,
req_inversion,
rsin_functionality,
rdiv_wf,
rless-int,
rless_wf,
rmul_preserves_req,
rinv_wf2,
decidable__equal_int,
full-omega-unsat,
intformnot_wf,
intformeq_wf,
int_formula_prop_not_lemma,
int_formula_prop_eq_lemma,
int_term_value_constant_lemma,
int_term_value_mul_lemma,
int_formula_prop_wf,
radd_functionality,
int-rdiv-req,
req_transitivity,
int-rinv-cancel
Rules used in proof :
sqequalSubstitution,
sqequalTransitivity,
computationStep,
sqequalReflexivity,
isect_memberFormation_alt,
introduction,
cut,
extract_by_obid,
sqequalHypSubstitution,
isectElimination,
thin,
hypothesisEquality,
hypothesis,
closedConclusion,
natural_numberEquality,
dependent_set_memberEquality_alt,
lambdaFormation_alt,
instantiate,
cumulativity,
intEquality,
independent_isectElimination,
dependent_functionElimination,
equalityTransitivity,
equalitySymmetry,
independent_functionElimination,
voidElimination,
equalityIstype,
baseClosed,
sqequalBase,
universeIsType,
because_Cache,
inhabitedIsType,
productElimination,
sqequalRule,
approximateComputation,
lambdaEquality_alt,
int_eqEquality,
isect_memberEquality_alt,
inrFormation_alt,
independent_pairFormation,
imageMemberEquality,
unionElimination,
dependent_pairFormation_alt
Latex:
\mforall{}[x:\mBbbR{}]. (rsin(x) = 2 * rsin((x)/2) * rcos((x)/2))
Date html generated:
2019_10_30-AM-11_41_53
Last ObjectModification:
2019_02_02-PM-01_51_31
Theory : reals_2
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