When solving an equation involving logs, I've gotten this far 4 = Log5x/log625x four is equal to log (base 5) x over log (base 625) x I know x is equal to 25. But how do I get to that answer not using guess and check?
Follow Math Help Forum on Facebook and Google+
Originally Posted by jsmith90210 When solving an equation involving logs, I've gotten this far 4 = Log5x/log625x four is equal to log (base 5) x over log (base 625) x I know x is equal to 25. But how do I get to that answer not using guess and check? First,U should know Log 625 X= (log 5 x)/(log 5 625) ,So U can solve it.
Originally Posted by jsmith90210 [SIZE=2]four is equal to log (base 5) x over log (base 625) x Since 625 = 5^4, then the change-of-base formula can prove helpful: . . . . . Then apply a log rule and the definition of logs to convert to just "4".
Excuse my ignorance, but how does that help me. Of course which would leave: (Log(base 5) x) OVER (log(base 5) x / 4) on one side and 4 on the other side of course 4 = 4
Nevermind, I should have seen this. The answer is actually x = 5^n, where n > 1
View Tag Cloud