Nuprl Lemma : rcos-radd

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


Proof




Definitions occuring in Statement :  rcos: rcos(x),  rsin: rsin(x),  rsub: x - y,  req: x = y,  rmul: a * b,  radd: a + b,  real: ℝ,  uall: ∀[x:A]. B[x]
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  so_lambda: λ2x.t[x],  rfun: I ⟶ℝ,  prop: ℙ,  so_apply: x[s],  rfun-eq: rfun-eq(I;f;g),  all: ∀x:A. B[x],  top: Top,  true: True,  rcos: rcos(x),  approx-arg: approx-arg(f;B;x),  accelerate: accelerate(k;f),  rsub: x - y,  radd: a + b,  r-ap: f(x),  rev_uimplies: rev_uimplies(P;Q),  and: P ∧ Q,  uiff: uiff(P;Q),  uimplies: b supposing a,  itermConstant: "const",  req_int_terms: t1 ≡ t2,  false: False,  not: ¬A
Lemmas referenced :  derivative_unique,  riiint_wf,  iproper-riiint,  rsin_wf,  radd_wf,  real_wf,  i-member_wf,  rcos_wf,  rsub_wf,  rmul_wf,  member_riiint_lemma,  true_wf,  req_witness,  rcos_functionality,  req_functionality,  req_weakening,  deriviative-rsin,  req_wf,  derivative-function-radd-const,  deriviative-rcos,  derivative-const-mul2,  derivative-add,  rminus_wf,  set_wf,  real_term_polynomial,  itermSubtract_wf,  itermAdd_wf,  itermMultiply_wf,  itermVar_wf,  itermMinus_wf,  int-to-real_wf,  real_term_value_const_lemma,  real_term_value_sub_lemma,  real_term_value_add_lemma,  real_term_value_mul_lemma,  real_term_value_var_lemma,  real_term_value_minus_lemma,  req-iff-rsub-is-0,  derivative_functionality,  rsin-radd
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesis,  independent_functionElimination,  sqequalRule,  lambdaEquality,  setElimination,  rename,  hypothesisEquality,  setEquality,  because_Cache,  dependent_functionElimination,  isect_memberEquality,  voidElimination,  voidEquality,  dependent_set_memberEquality,  natural_numberEquality,  productElimination,  independent_isectElimination,  lambdaFormation,  computeAll,  int_eqEquality,  intEquality

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



Date html generated: 2017_10_04-PM-10_21_35
Last ObjectModification: 2017_07_28-AM-08_48_19

Theory : reals_2


Home Index