Metamath Proof Explorer


Theorem dvmptsub

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

Ref Expression
Hypotheses dvmptadd.s φ S
dvmptadd.a φ x X A
dvmptadd.b φ x X B V
dvmptadd.da φ dx X A dS x = x X B
dvmptsub.c φ x X C
dvmptsub.d φ x X D W
dvmptsub.dc φ dx X C dS x = x X D
Assertion dvmptsub φ dx X A C dS x = x X B D

Proof

Step Hyp Ref Expression
1 dvmptadd.s φ S
2 dvmptadd.a φ x X A
3 dvmptadd.b φ x X B V
4 dvmptadd.da φ dx X A dS x = x X B
5 dvmptsub.c φ x X C
6 dvmptsub.d φ x X D W
7 dvmptsub.dc φ dx X C dS x = x X D
8 5 negcld φ x X C
9 negex D V
10 9 a1i φ x X D V
11 1 5 6 7 dvmptneg φ dx X C dS x = x X D
12 1 2 3 4 8 10 11 dvmptadd φ dx X A + C dS x = x X B + D
13 2 5 negsubd φ x X A + C = A C
14 13 mpteq2dva φ x X A + C = x X A C
15 14 oveq2d φ dx X A + C dS x = dx X A C dS x
16 1 2 3 4 dvmptcl φ x X B
17 1 5 6 7 dvmptcl φ x X D
18 16 17 negsubd φ x X B + D = B D
19 18 mpteq2dva φ x X B + D = x X B D
20 12 15 19 3eqtr3d φ dx X A C dS x = x X B D