Metamath Proof Explorer


Theorem xltmul1

Description: Extended real version of ltmul1 . (Contributed by Mario Carneiro, 20-Aug-2015)

Ref Expression
Assertion xltmul1 A * B * C + A < B A 𝑒 C < B 𝑒 C

Proof

Step Hyp Ref Expression
1 xlemul1 B * A * C + B A B 𝑒 C A 𝑒 C
2 1 3com12 A * B * C + B A B 𝑒 C A 𝑒 C
3 2 notbid A * B * C + ¬ B A ¬ B 𝑒 C A 𝑒 C
4 xrltnle A * B * A < B ¬ B A
5 4 3adant3 A * B * C + A < B ¬ B A
6 simp1 A * B * C + A *
7 rpxr C + C *
8 7 3ad2ant3 A * B * C + C *
9 xmulcl A * C * A 𝑒 C *
10 6 8 9 syl2anc A * B * C + A 𝑒 C *
11 simp2 A * B * C + B *
12 xmulcl B * C * B 𝑒 C *
13 11 8 12 syl2anc A * B * C + B 𝑒 C *
14 xrltnle A 𝑒 C * B 𝑒 C * A 𝑒 C < B 𝑒 C ¬ B 𝑒 C A 𝑒 C
15 10 13 14 syl2anc A * B * C + A 𝑒 C < B 𝑒 C ¬ B 𝑒 C A 𝑒 C
16 3 5 15 3bitr4d A * B * C + A < B A 𝑒 C < B 𝑒 C