M Materia New member Joined Apr 27, 2006 Messages 1 Apr 27, 2006 #1 I'm having trouble getting started on these two log problems. Any little bit of help is appreciated. Problem 1: log4(x+3) + log4(x-3) = 2 Problem 2: log3^x - log3^4 = 2
I'm having trouble getting started on these two log problems. Any little bit of help is appreciated. Problem 1: log4(x+3) + log4(x-3) = 2 Problem 2: log3^x - log3^4 = 2
G galactus Super Moderator Staff member Joined Sep 28, 2005 Messages 7,203 Apr 27, 2006 #2 For #1 law of logs: \(\displaystyle \L\\log_{4}(x+3)+log_{4}(x-3)=log_{4}((x-3)(x+3))\) So, you have: \(\displaystyle \L\\log_{4}((x+3)(x-3))=2\) Another log law; \(\displaystyle \L\\(x+3)(x-3)=4^{2}=16\) Solve for x.
For #1 law of logs: \(\displaystyle \L\\log_{4}(x+3)+log_{4}(x-3)=log_{4}((x-3)(x+3))\) So, you have: \(\displaystyle \L\\log_{4}((x+3)(x-3))=2\) Another log law; \(\displaystyle \L\\(x+3)(x-3)=4^{2}=16\) Solve for x.
