Let X, x, y and p be given.
Assume Hfun: function_on p unit_interval X.
Assume H0: apply_fun p 0 = x.
Assume H1: apply_fun p 1 = y.
We prove the intermediate claim Hpair0: function_on p unit_interval X apply_fun p 0 = x.
An exact proof term for the current goal is (andI (function_on p unit_interval X) (apply_fun p 0 = x) Hfun H0).
An exact proof term for the current goal is (andI (function_on p unit_interval X apply_fun p 0 = x) (apply_fun p 1 = y) Hpair0 H1).