FA-16128 / Floating-point arithmetic / Member archive

Rationalized square-root increment uses the wrong conjugate · case 03

Rationalized square-root increment uses the wrong conjugate.

Member previewVariant 3 · 3 implementations · 8 checks per implementation

Case contract

Evaluate sqrt(1+x)-1 stably for finite x >= -1. Finite results are rendered to eleven significant decimal digits; modeled domain violations and arithmetic errors are explicit strings.

Why this case matters

An offline floating representation model isolates a reproducible arithmetic fault.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
tiny positive	`"arithmetic-error"`	`"1.301042607e-18"`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.