The ¬$xj rule can be applied to give:

¬$x$y[Fx®Rxy] "x¬$y[Fx®Rxy]

Neither rule can be applied. The formula does not begin with ¬" or ¬$.

The ¬"xj rule can be applied. The following in a possible result:

(But one could, if one wished, add $y¬Rya to just one of the branches.)

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