Beginning of Section SurrealDiv
Notation. We use - as a prefix operator with priority 358 corresponding to applying term minus_SNo.
Notation. We use + as an infix operator with priority 360 and which associates to the right corresponding to applying term add_SNo.
Notation. We use * as an infix operator with priority 355 and which associates to the right corresponding to applying term mul_SNo.
Notation. We use < as an infix operator with priority 490 and no associativity corresponding to applying term SNoLt.
Notation. We use as an infix operator with priority 490 and no associativity corresponding to applying term SNoLe.
Notation. We use ^ as an infix operator with priority 342 and which associates to the right corresponding to applying term exp_SNo_nat.
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(*** Part 8 ***)
L19
Definition. We define SNoL_pos to be λx ⇒ {w ∈ SNoL x|0 < w} of type setset.
L21
Theorem. (SNo_recip_pos_pos)
∀x xi, SNo xSNo xi0 < xx * xi = 10 < xi
Proof:
Proof not loaded.
L43
Theorem. (SNo_recip_lem1)
∀x x' x'i y y', SNo x0 < xx' SNoL_pos xSNo x'ix' * x'i = 1SNo yx * y < 1SNo y'1 + - x * y' = (1 + - x * y) * (x' + - x) * x'i1 < x * y'
Proof:
Proof not loaded.
L89
Theorem. (SNo_recip_lem2)
∀x x' x'i y y', SNo x0 < xx' SNoL_pos xSNo x'ix' * x'i = 1SNo y1 < x * ySNo y'1 + - x * y' = (1 + - x * y) * (x' + - x) * x'ix * y' < 1
Proof:
Proof not loaded.
L135
Theorem. (SNo_recip_lem3)
∀x x' x'i y y', SNo x0 < xx' SNoR xSNo x'ix' * x'i = 1SNo yx * y < 1SNo y'1 + - x * y' = (1 + - x * y) * (x' + - x) * x'ix * y' < 1
Proof:
Proof not loaded.
L180
Theorem. (SNo_recip_lem4)
∀x x' x'i y y', SNo x0 < xx' SNoR xSNo x'ix' * x'i = 1SNo y1 < x * ySNo y'1 + - x * y' = (1 + - x * y) * (x' + - x) * x'i1 < x * y'
Proof:
Proof not loaded.
L225
Definition. We define SNo_recipauxset to be λY x X g ⇒ y ∈ Y{(1 + (x' + - x) * y) * g x'|x' ∈ X} of type setsetset(setset)set.
L227
Theorem. (SNo_recipauxset_I)
∀Y x X, ∀g : setset, ∀yY, ∀x'X, (1 + (x' + - x) * y) * g x' SNo_recipauxset Y x X g
Proof:
Proof not loaded.
L236
Theorem. (SNo_recipauxset_E)
∀Y x X, ∀g : setset, ∀zSNo_recipauxset Y x X g, ∀p : prop, (∀yY, ∀x'X, z = (1 + (x' + - x) * y) * g x'p)p
Proof:
Proof not loaded.
L248
Theorem. (SNo_recipauxset_ext)
∀Y x X, ∀g h : setset, (∀x'X, g x' = h x')SNo_recipauxset Y x X g = SNo_recipauxset Y x X h
Proof:
Proof not loaded.
L262
Definition. We define SNo_recipaux to be λx g ⇒ nat_primrec ({0},0) (λk p ⇒ (p 0SNo_recipauxset (p 0) x (SNoR x) gSNo_recipauxset (p 1) x (SNoL_pos x) g,p 1SNo_recipauxset (p 0) x (SNoL_pos x) gSNo_recipauxset (p 1) x (SNoR x) g)) of type set(setset)setset.
L270
Theorem. (SNo_recipaux_0)
∀x, ∀g : setset, SNo_recipaux x g 0 = ({0},0)
Proof:
Proof not loaded.
L279
Theorem. (SNo_recipaux_S)
∀x, ∀g : setset, ∀n, nat_p nSNo_recipaux x g (ordsucc n) = (SNo_recipaux x g n 0SNo_recipauxset (SNo_recipaux x g n 0) x (SNoR x) gSNo_recipauxset (SNo_recipaux x g n 1) x (SNoL_pos x) g,SNo_recipaux x g n 1SNo_recipauxset (SNo_recipaux x g n 0) x (SNoL_pos x) gSNo_recipauxset (SNo_recipaux x g n 1) x (SNoR x) g)
Proof:
Proof not loaded.
L293
Theorem. (SNo_recipaux_lem1)
∀x, SNo x0 < x∀g : setset, (∀x'SNoS_ (SNoLev x), 0 < x'SNo (g x')x' * g x' = 1)∀k, nat_p k(∀ySNo_recipaux x g k 0, SNo yx * y < 1)(∀ySNo_recipaux x g k 1, SNo y1 < x * y)
Proof:
Proof not loaded.
L536
Theorem. (SNo_recipaux_lem2)
∀x, SNo x0 < x∀g : setset, (∀x'SNoS_ (SNoLev x), 0 < x'SNo (g x')x' * g x' = 1)SNoCutP (k ∈ ωSNo_recipaux x g k 0) (k ∈ ωSNo_recipaux x g k 1)
Proof:
Proof not loaded.
L597
Theorem. (SNo_recipaux_ext)
∀x, SNo x∀g h : setset, (∀x'SNoS_ (SNoLev x), g x' = h x')∀k, nat_p kSNo_recipaux x g k = SNo_recipaux x h k
Proof:
Proof not loaded.
Beginning of Section recip_SNo_pos
L687
Let G : set(setset)setλx g ⇒ SNoCut (k ∈ ωSNo_recipaux x g k 0) (k ∈ ωSNo_recipaux x g k 1)
L689
Definition. We define recip_SNo_pos to be SNo_rec_i G of type setset.
L691
Theorem. (recip_SNo_pos_eq)
∀x, SNo xrecip_SNo_pos x = G x recip_SNo_pos
Proof:
Proof not loaded.
L716
Theorem. (recip_SNo_pos_prop1)
∀x, SNo x0 < xSNo (recip_SNo_pos x)x * recip_SNo_pos x = 1
Proof:
Proof not loaded.
L1339
Theorem. (SNo_recip_SNo_pos)
∀x, SNo x0 < xSNo (recip_SNo_pos x)
Proof:
Proof not loaded.
L1344
Theorem. (recip_SNo_pos_invR)
∀x, SNo x0 < xx * recip_SNo_pos x = 1
Proof:
Proof not loaded.
L1349
Proof:
Proof not loaded.
L1357
Theorem. (recip_SNo_pos_is_pos)
∀x, SNo x0 < x0 < recip_SNo_pos x
Proof:
Proof not loaded.
L1382
Theorem. (recip_SNo_pos_invol)
∀x, SNo x0 < xrecip_SNo_pos (recip_SNo_pos x) = x
Proof:
Proof not loaded.
L1405
Theorem. (recip_SNo_pos_eps_)
∀n, nat_p nrecip_SNo_pos (eps_ n) = 2 ^ n
Proof:
Proof not loaded.
L1426
Theorem. (recip_SNo_pos_pow_2)
∀n, nat_p nrecip_SNo_pos (2 ^ n) = eps_ n
Proof:
Proof not loaded.
L1432
Theorem. (recip_SNo_pos_2)
recip_SNo_pos 2 = eps_ 1
Proof:
Proof not loaded.
End of Section recip_SNo_pos
L1439
Definition. We define recip_SNo to be λx ⇒ if 0 < x then recip_SNo_pos x else if x < 0 then - recip_SNo_pos (- x) else 0 of type setset.
L1441
Theorem. (recip_SNo_poscase)
∀x, 0 < xrecip_SNo x = recip_SNo_pos x
Proof:
Proof not loaded.
L1446
Theorem. (recip_SNo_negcase)
∀x, SNo xx < 0recip_SNo x = - recip_SNo_pos (- x)
Proof:
Proof not loaded.
L1458
Theorem. (recip_SNo_0)
recip_SNo 0 = 0
Proof:
Proof not loaded.
L1465
Theorem. (recip_SNo_1)
recip_SNo 1 = 1
Proof:
Proof not loaded.
L1470
Theorem. (SNo_recip_SNo)
∀x, SNo xSNo (recip_SNo x)
Proof:
Proof not loaded.
L1490
Theorem. (recip_SNo_invR)
∀x, SNo xx0x * recip_SNo x = 1
Proof:
Proof not loaded.
L1512
Theorem. (recip_SNo_invL)
∀x, SNo xx0recip_SNo x * x = 1
Proof:
Proof not loaded.
L1519
Theorem. (recip_SNo_eps_)
∀n, nat_p nrecip_SNo (eps_ n) = 2 ^ n
Proof:
Proof not loaded.
L1525
Theorem. (recip_SNo_pow_2)
∀n, nat_p nrecip_SNo (2 ^ n) = eps_ n
Proof:
Proof not loaded.
L1533
Theorem. (recip_SNo_2)
recip_SNo 2 = eps_ 1
Proof:
Proof not loaded.
L1538
Theorem. (recip_SNo_invol)
∀x, SNo xrecip_SNo (recip_SNo x) = x
Proof:
Proof not loaded.
L1575
Theorem. (recip_SNo_of_pos_is_pos)
∀x, SNo x0 < x0 < recip_SNo x
Proof:
Proof not loaded.
L1581
Theorem. (recip_SNo_neg')
∀x, SNo xx < 0recip_SNo x < 0
Proof:
Proof not loaded.
L1607
Definition. We define div_SNo to be λx y ⇒ x * recip_SNo y of type setsetset.
Notation. We use :/: as an infix operator with priority 353 and no associativity corresponding to applying term div_SNo.
L1611
Theorem. (SNo_div_SNo)
∀x y, SNo xSNo ySNo (x :/: y)
Proof:
Proof not loaded.
L1617
Theorem. (div_SNo_0_num)
∀x, SNo x0 :/: x = 0
Proof:
Proof not loaded.
L1622
Theorem. (div_SNo_0_denum)
∀x, SNo xx :/: 0 = 0
Proof:
Proof not loaded.
L1629
Theorem. (mul_div_SNo_invL)
∀x y, SNo xSNo yy0(x :/: y) * y = x
Proof:
Proof not loaded.
L1639
Theorem. (mul_div_SNo_invR)
∀x y, SNo xSNo yy0y * (x :/: y) = x
Proof:
Proof not loaded.
L1645
Theorem. (mul_div_SNo_R)
∀x y z, SNo xSNo ySNo z(x :/: y) * z = (x * z) :/: y
Proof:
Proof not loaded.
L1666
Theorem. (mul_div_SNo_L)
∀x y z, SNo xSNo ySNo zz * (x :/: y) = (z * x) :/: y
Proof:
Proof not loaded.
L1674
Theorem. (div_mul_SNo_invL)
∀x y, SNo xSNo yy0(x * y) :/: y = x
Proof:
Proof not loaded.
L1681
Theorem. (div_div_SNo)
∀x y z, SNo xSNo ySNo z(x :/: y) :/: z = x :/: (y * z)
Proof:
Proof not loaded.
L1731
Theorem. (mul_div_SNo_both)
∀x y z w, SNo xSNo ySNo zSNo w(x :/: y) * (z :/: w) = (x * z) :/: (y * w)
Proof:
Proof not loaded.
L1740
Theorem. (recip_SNo_pos_pos)
∀x, SNo x0 < x0 < recip_SNo_pos x
Proof:
Proof not loaded.
L1756
Theorem. (recip_SNo_of_neg_is_neg)
∀x, SNo xx < 0recip_SNo x < 0
Proof:
Proof not loaded.
L1777
Theorem. (div_SNo_pos_pos)
∀x y, SNo xSNo y0 < x0 < y0 < x :/: y
Proof:
Proof not loaded.
L1785
Theorem. (div_SNo_neg_neg)
∀x y, SNo xSNo yx < 0y < 00 < x :/: y
Proof:
Proof not loaded.
L1793
Theorem. (div_SNo_pos_neg)
∀x y, SNo xSNo y0 < xy < 0x :/: y < 0
Proof:
Proof not loaded.
L1801
Theorem. (div_SNo_neg_pos)
∀x y, SNo xSNo yx < 00 < yx :/: y < 0
Proof:
Proof not loaded.
L1809
Theorem. (div_SNo_pos_LtL)
∀x y z, SNo xSNo ySNo z0 < yx < z * yx :/: y < z
Proof:
Proof not loaded.
L1830
Theorem. (div_SNo_pos_LtR)
∀x y z, SNo xSNo ySNo z0 < yz * y < xz < x :/: y
Proof:
Proof not loaded.
L1851
Theorem. (div_SNo_pos_LtL')
∀x y z, SNo xSNo ySNo z0 < yx :/: y < zx < z * y
Proof:
Proof not loaded.
L1870
Theorem. (div_SNo_pos_LtR')
∀x y z, SNo xSNo ySNo z0 < yz < x :/: yz * y < x
Proof:
Proof not loaded.
L1889
Theorem. (mul_div_SNo_nonzero_eq)
∀x y z, SNo xSNo ySNo zy0x = y * zx :/: y = z
Proof:
Proof not loaded.
End of Section SurrealDiv