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2t2e4
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Metamath Proof Explorer
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Theorem
2t2e4
Description:
2 times 2 equals 4.
(Contributed by
NM
, 1-Aug-1999)
Ref
Expression
Assertion
2t2e4
⊢
2
⋅
2
=
4
Proof
Step
Hyp
Ref
Expression
1
2cn
⊢
2
∈
ℂ
2
1
2timesi
⊢
2
⋅
2
=
2
+
2
3
2p2e4
⊢
2
+
2
=
4
4
2
3
eqtri
⊢
2
⋅
2
=
4