Nuprl Lemma : rsin-rsub

∀[x,y:ℝ].  (rsin(x - y) = ((rsin(x) * rcos(y)) - rcos(x) * rsin(y)))


Proof




Definitions occuring in Statement :  rcos: rcos(x),  rsin: rsin(x),  rsub: x - y,  req: x = y,  rmul: a * b,  real: ℝ,  uall: ∀[x:A]. B[x]
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  rsub: x - y,  implies: P ⇒ Q,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  all: ∀x:A. B[x],  rev_uimplies: rev_uimplies(P;Q),  req_int_terms: t1 ≡ t2,  false: False,  not: ¬A,  top: Top
Lemmas referenced :  req_witness,  rsin_wf,  rsub_wf,  rmul_wf,  rcos_wf,  real_wf,  radd_wf,  rminus_wf,  itermSubtract_wf,  itermAdd_wf,  itermMultiply_wf,  itermVar_wf,  itermMinus_wf,  req-iff-rsub-is-0,  req_functionality,  req_transitivity,  rsin-radd,  radd_functionality,  rmul_functionality,  req_weakening,  rsin-rminus,  rcos-rminus,  real_polynomial_null,  int-to-real_wf,  istype-int,  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_minus_lemma,  real_term_value_const_lemma
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  independent_functionElimination,  inhabitedIsType,  sqequalRule,  isect_memberEquality_alt,  because_Cache,  isectIsTypeImplies,  universeIsType,  natural_numberEquality,  productElimination,  independent_isectElimination,  dependent_functionElimination,  approximateComputation,  lambdaEquality_alt,  int_eqEquality,  voidElimination

Latex:
\mforall{}[x,y:\mBbbR{}].    (rsin(x  -  y)  =  ((rsin(x)  *  rcos(y))  -  rcos(x)  *  rsin(y)))



Date html generated: 2019_10_30-AM-11_41_48
Last ObjectModification: 2019_05_17-AM-11_26_30

Theory : reals_2


Home Index