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Metamath Proof Explorer

Theorem sq2

Description: The square of 2 is 4. (Contributed by NM, 22-Aug-1999)

Ref Expression
Assertion sq2 
|- ( 2 ^ 2 ) = 4

Proof

Step Hyp Ref Expression
1 2cn 
 |-  2 e. CC
2 1 sqvali 
 |-  ( 2 ^ 2 ) = ( 2 x. 2 )
3 2t2e4 
 |-  ( 2 x. 2 ) = 4
4 2 3 eqtri 
 |-  ( 2 ^ 2 ) = 4