Let z be given.
Assume Hz.
We will prove SNo (sqrt_SNo_nonneg (abs_sqr_CSNo z)).
Apply SNo_sqrt_SNo_nonneg to the current goal.
An exact proof term for the current goal is SNo_abs_sqr_CSNo z Hz.
An exact proof term for the current goal is abs_sqr_CSNo_nonneg z Hz.