Database
REAL AND COMPLEX NUMBERS
Order sets
Infinity and the extended real number system (cont.)
xaddlid
Next ⟩
xaddridd
Metamath Proof Explorer
Ascii
Unicode
Theorem
xaddlid
Description:
Extended real version of
addlid
.
(Contributed by
Mario Carneiro
, 20-Aug-2015)
Ref
Expression
Assertion
xaddlid
⊢
A
∈
ℝ
*
→
0
+
𝑒
A
=
A
Proof
Step
Hyp
Ref
Expression
1
0xr
⊢
0
∈
ℝ
*
2
xaddcom
⊢
0
∈
ℝ
*
∧
A
∈
ℝ
*
→
0
+
𝑒
A
=
A
+
𝑒
0
3
1
2
mpan
⊢
A
∈
ℝ
*
→
0
+
𝑒
A
=
A
+
𝑒
0
4
xaddrid
⊢
A
∈
ℝ
*
→
A
+
𝑒
0
=
A
5
3
4
eqtrd
⊢
A
∈
ℝ
*
→
0
+
𝑒
A
=
A