_3_ represents subscript
2007-09-16 12:43:33 · 4 answers · asked by Paulllll C 3 in Science & Mathematics ➔ Mathematics
log(A) - log(B) = log(A/B)
log_3_(x-2) - log_3_(x-4) = 2
log_3_[(x-2)/(x-4)] = 2
(x-2)/(x-4) = 3^2 = 9
x-2 = 9*(x-4)
x-2 = 9x-36
34 = 8x
x = 17/4
2007-09-16 12:51:17 · answer #1 · answered by np_rt 4 · 0⤊ 0⤋
Logs that are subtracted can be written as a single log of a division: log 3 [(x-2)/(x-4)] = 2 which is log 3 9
so now (x-2)/(x-4) = 9 and you can cross multiply to solve.
2007-09-16 19:51:31 · answer #2 · answered by hayharbr 7 · 0⤊ 0⤋
This type, you don't . Just remember that in any base log, log a - log b = log (a/b). So................
Log (x-2)/(x-4) = 2
Also, if b is the base of the log, b^(log_b_ (x)) = x
So...............
(x-2)/(x-4) = 9
This doesn't need a calculator.
2007-09-17 20:25:01 · answer #3 · answered by cattbarf 7 · 1⤊ 0⤋
np_rt has the right answer, there is no point in trying to tell you because i would do exactly what he did.
2007-09-16 19:55:28 · answer #4 · answered by YourMom 2 · 0⤊ 0⤋