Nuprl Lemma : square-is-zero
∀x:ℝ. ((x * x) = r0
⇐⇒ x = r0)
Proof
Definitions occuring in Statement :
req: x = y
,
rmul: a * b
,
int-to-real: r(n)
,
real: ℝ
,
all: ∀x:A. B[x]
,
iff: P
⇐⇒ Q
,
natural_number: $n
Definitions unfolded in proof :
all: ∀x:A. B[x]
,
iff: P
⇐⇒ Q
,
and: P ∧ Q
,
implies: P
⇒ Q
,
member: t ∈ T
,
uall: ∀[x:A]. B[x]
,
prop: ℙ
,
rev_implies: P
⇐ Q
,
guard: {T}
,
uimplies: b supposing a
,
nat: ℕ
,
le: A ≤ B
,
less_than': less_than'(a;b)
,
not: ¬A
,
false: False
,
uiff: uiff(P;Q)
,
squash: ↓T
,
nat_plus: ℕ+
,
decidable: Dec(P)
,
or: P ∨ Q
,
satisfiable_int_formula: satisfiable_int_formula(fmla)
,
exists: ∃x:A. B[x]
,
true: True
,
subtype_rel: A ⊆r B
,
rneq: x ≠ y
,
rless: x < y
,
sq_exists: ∃x:A [B[x]]
,
less_than: a < b
Latex:
\mforall{}x:\mBbbR{}. ((x * x) = r0 \mLeftarrow{}{}\mRightarrow{} x = r0)
Date html generated:
2020_05_20-AM-11_08_10
Last ObjectModification:
2019_12_14-PM-00_56_01
Theory : reals
Home
Index