Posted by logarithms on Monday, January 14, 2008 at 1:07pm.
how do you perform this??
log x + log(x+3) = 1

algebra  Reiny, Monday, January 14, 2008 at 1:13pm
One of the main rules of logs is
Log(AB) = Log A + Log B, as long as the base is the same
so log x + log(x+3) = 1
Log (x(x+3)) = 1
Log(x^2 + 3x) = 1
x^2 + 3x = 10^1
x^2 + 3x  10 = 0
(x+5)(x2) = 0
x=5 or x=2
but in log x , x must be greater than 0
so x = 2
Answer This Question
Related Questions
 math  Logarithm!!! Select all of the following that are true statements: (a) ...
 Algebra 2  how do not understand how to do this Log X + Lob (X3) = 1 I know I ...
 Math Help Please  Which of the following expressions is equal to log (x sqrty...
 Mathematics  Prove that log a, log ar, log ar^2 is an a.p. Is the following ...
 college algebra  Write expression as one logarithm and simplify if appropriate...
 math(Please help)  1) use the properties of logarithms to simplify the ...
 math  write as a single logarithm: 2logbase3(1/x)+(1/3)logbase3(square root of...
 Algebra 2  Explain the difference between log base b (mn) and ( log base b of ...
 Precaculculus  Suppose you are told that log(2)=0.3562 and log(3)=0.5646. All ...
 Trigonometry  This is a logs question If u=x/y^2, which expression is ...
More Related Questions