Metamath Proof Explorer


Theorem dvmptid

Description: Function-builder for derivative: derivative of the identity. (Contributed by Mario Carneiro, 1-Sep-2014) (Revised by Mario Carneiro, 11-Feb-2015)

Ref Expression
Hypothesis dvmptid.1 ( 𝜑𝑆 ∈ { ℝ , ℂ } )
Assertion dvmptid ( 𝜑 → ( 𝑆 D ( 𝑥𝑆𝑥 ) ) = ( 𝑥𝑆 ↦ 1 ) )

Proof

Step Hyp Ref Expression
1 dvmptid.1 ( 𝜑𝑆 ∈ { ℝ , ℂ } )
2 eqid ( TopOpen ‘ ℂfld ) = ( TopOpen ‘ ℂfld )
3 2 cnfldtopon ( TopOpen ‘ ℂfld ) ∈ ( TopOn ‘ ℂ )
4 toponmax ( ( TopOpen ‘ ℂfld ) ∈ ( TopOn ‘ ℂ ) → ℂ ∈ ( TopOpen ‘ ℂfld ) )
5 3 4 mp1i ( 𝜑 → ℂ ∈ ( TopOpen ‘ ℂfld ) )
6 recnprss ( 𝑆 ∈ { ℝ , ℂ } → 𝑆 ⊆ ℂ )
7 1 6 syl ( 𝜑𝑆 ⊆ ℂ )
8 df-ss ( 𝑆 ⊆ ℂ ↔ ( 𝑆 ∩ ℂ ) = 𝑆 )
9 7 8 sylib ( 𝜑 → ( 𝑆 ∩ ℂ ) = 𝑆 )
10 simpr ( ( 𝜑𝑥 ∈ ℂ ) → 𝑥 ∈ ℂ )
11 1cnd ( ( 𝜑𝑥 ∈ ℂ ) → 1 ∈ ℂ )
12 mptresid ( I ↾ ℂ ) = ( 𝑥 ∈ ℂ ↦ 𝑥 )
13 12 eqcomi ( 𝑥 ∈ ℂ ↦ 𝑥 ) = ( I ↾ ℂ )
14 13 oveq2i ( ℂ D ( 𝑥 ∈ ℂ ↦ 𝑥 ) ) = ( ℂ D ( I ↾ ℂ ) )
15 dvid ( ℂ D ( I ↾ ℂ ) ) = ( ℂ × { 1 } )
16 fconstmpt ( ℂ × { 1 } ) = ( 𝑥 ∈ ℂ ↦ 1 )
17 14 15 16 3eqtri ( ℂ D ( 𝑥 ∈ ℂ ↦ 𝑥 ) ) = ( 𝑥 ∈ ℂ ↦ 1 )
18 17 a1i ( 𝜑 → ( ℂ D ( 𝑥 ∈ ℂ ↦ 𝑥 ) ) = ( 𝑥 ∈ ℂ ↦ 1 ) )
19 2 1 5 9 10 11 18 dvmptres3 ( 𝜑 → ( 𝑆 D ( 𝑥𝑆𝑥 ) ) = ( 𝑥𝑆 ↦ 1 ) )