I reviewed this and figured out a more traditional approach:
Base change formula applied twice:
Use x=y^n, as in previous post...
Sorry, my notation was sloppy. What I meant was (don't we wish we could do this on exams):
A)Let log(x)z = log of z in base x
One more approach
Use (x) for base.
Since 1/4 = 4^-1, and 4 =2^2
log(1/4) = -log(4)
log(4) = 1/2 log(2)
log(1/4) = (-1/2)log(2) = (-1/2) *...