Consider the following premises. p <-> t_1. p -> t_1. Can we infer ~(t_1 <-> p) from them? If possible, name the inference rules being used at each step.
 From p <-> t_1 we can infer t_1 -> p via biconditional elimination. Finally, from t_1 -> p, p -> t_1 we can infer t_1 <-> p via biconditional introduction, which contradicts ~(t_1 <-> p). Therefore, the answer is no.