MathDB
1968 AMC 12 #23 - Logarithmic Equation

Source:

January 1, 2012
logarithmsAMC

Problem Statement

If all the logarithms are real numbers, the equality log(x+3)+log(x1)=log(x22x3) \log(x+3)+\log (x-1) = \log (x^2-2x-3) is satisfied for:
<spanclass=latexbold>(A)</span> all real values of x<spanclass=latexbold>(B)</span> no real values of x<spanclass=latexbold>(C)</span> all real values of x except x=0<spanclass=latexbold>(D)</span> no real values of x except x=0<spanclass=latexbold>(E)</span> all real values of x except x=1<span class='latex-bold'>(A)</span>\ \text{all real values of}\ x \\ \qquad<span class='latex-bold'>(B)</span>\ \text{no real values of}\ x \\ \qquad<span class='latex-bold'>(C)</span>\ \text{all real values of}\ x\ \text{except}\ x=0 \\ \qquad<span class='latex-bold'>(D)</span>\ \text{no real values of}\ x\ \text{except}\ x=0 \\ \qquad<span class='latex-bold'>(E)</span>\ \text{all real values of}\ x\ \text{except}\ x=1