已知 log (a) ab=1/p ,则 log (ab) a/b=-- --.

log (a) ab=1/p ,Log(a)a+Log(a)b=1/p,1+Log(a)b=1/p
Log(a)b=(1-p)/p
log (ab) a/b=(换底)
=[Log(a)a/b]/Log(a)(ab)
=[Log(a)a/b]/(1/p)
=p[Log(a)a/b]
=p[LOg(a)a-LOg(a)b]
=p[1-(1-p)/p]
=p-(1-p)
=2p-1