Metamath Proof Explorer


Theorem lcmineqlem7

Description: Derivative of 1-x for chain rule application. (Contributed by metakunt, 12-May-2024)

Ref Expression
Assertion lcmineqlem7 dx 1 x d x = x 1

Proof

Step Hyp Ref Expression
1 cnelprrecn
2 1 a1i
3 1cnd x 1
4 0cnd x 0
5 1cnd 1
6 2 5 dvmptc dx 1 d x = x 0
7 simpr x x
8 2 dvmptid dx x d x = x 1
9 2 3 4 6 7 3 8 dvmptsub dx 1 x d x = x 0 1
10 df-neg 1 = 0 1
11 10 a1i 1 = 0 1
12 11 eqcomd 0 1 = 1
13 12 mpteq2dv x 0 1 = x 1
14 9 13 eqtrd dx 1 x d x = x 1
15 14 mptru dx 1 x d x = x 1