BT00PV

mul_le_mul

Alpha body-checked ยท checked-use disabled

Multiplication is monotone in both natural-number arguments.

Exact expanded PA statement

forall a b c d. (exists bpo_gap_mul_left. bpo_gap_mul_left + (a) = (b)) -> (exists bpo_gap_mul_right. bpo_gap_mul_right + (c) = (d)) -> (exists bpo_gap_mul_result. bpo_gap_mul_result + (a * c) = (b * d))

Structural proof guide

Multiplication is monotone in both natural-number arguments.

Direct prerequisites: mul_le_mul_right, mul_le_mul_left, le_trans. The authored body proceeds by intermediate claims (2).

Proof neighborhood

Direct dependencies

Direct dependents

Formal native tactic body

Dependencies are hypotheses of this body receipt. The focused endpoint audits separately check the complete empty-context certificates.

  1. 0001intro a
  2. 0002intro b
  3. 0003intro c
  4. 0004intro d
  5. 0005intro hab
  6. 0006intro hcd
  7. 0007have hacbc : exists k. k + a * c = b * c
  8. 0008specialize mul_le_mul_right a
  9. 0009specialize mul_le_mul_right b
  10. 0010specialize mul_le_mul_right c
  11. 0011apply mul_le_mul_right
  12. 0012exact hab
  13. 0013have hbcbd : exists k. k + b * c = b * d
  14. 0014specialize mul_le_mul_left c
  15. 0015specialize mul_le_mul_left d
  16. 0016specialize mul_le_mul_left b
  17. 0017apply mul_le_mul_left
  18. 0018exact hcd
  19. 0019specialize le_trans (a * c)
  20. 0020specialize le_trans (b * c)
  21. 0021specialize le_trans (b * d)
  22. 0022apply le_trans
  23. 0023exact hacbc
  24. 0024exact hbcbd