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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 ∈ ℂ
2 1 sqvali ⊢ ( 2 ↑ 2 ) = ( 2 · 2 )
3 2t2e4 ⊢ ( 2 · 2 ) = 4
4 2 3 eqtri ⊢ ( 2 ↑ 2 ) = 4