Proof of `Extracting fresh label coefficients through pin quotients` (3rd statement)
groundedproofs/Lax342547Proofs/QuotientExtractors.lean · lax-342547
What this proof establishes
no assumptions
Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.
Description
Choose a linear section onto the image of the quotient composite. The kernel condition makes the prescribed output independent of that section. Extend from the image to the whole quotient vector space.