Metamath Proof Explorer


Theorem itgeq2dv

Description: Equality theorem for an integral. (Contributed by Mario Carneiro, 7-Jul-2014)

Ref Expression
Hypothesis itgeq2dv.1
|- ( ( ph /\ x e. A ) -> B = C )
Assertion itgeq2dv
|- ( ph -> S. A B _d x = S. A C _d x )

Proof

Step Hyp Ref Expression
1 itgeq2dv.1
 |-  ( ( ph /\ x e. A ) -> B = C )
2 1 ralrimiva
 |-  ( ph -> A. x e. A B = C )
3 itgeq2
 |-  ( A. x e. A B = C -> S. A B _d x = S. A C _d x )
4 2 3 syl
 |-  ( ph -> S. A B _d x = S. A C _d x )