SOLUTION: I need help with solving this logarithmic equation log5(x+1)+log5(x-1)=log5 8

Algebra.Com
Question 129923: I need help with solving this logarithmic equation
log5(x+1)+log5(x-1)=log5 8

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!



Combine the logs using the identity




Now raise both sides as exponents with bases of 5 to eliminate the logs on both sides


Foil


Subtract 8 from both sides



Factor the left side



Now set each factor equal to zero:
or

or Now solve for x in each case


So the possible answers are
or

However, the possible solution makes the argument of both logs negative.

So the only solution is

RELATED QUESTIONS

log5(log5... (answered by jsmallt9)
I need help solving this logarithmic equation... (answered by jim_thompson5910)
I need help solving this logarithmic equation... (answered by scott8148)
Hi i need help solving this problems: log5^1/25, log5^125, log3^1/9,... (answered by stanbon)
Solve the logarithmic equation for x. log5 6 + log5 x = log5 8 + log5(x −... (answered by stanbon,MathLover1)
Hello! Solve the logarithmic equation for x. log5 (x - 1) + log5 (x + 1) = 2... (answered by nerdybill)
log5 (x+3) + log5 (x-1) =... (answered by mouk)
log5(x+1)-log5(x-1)=2 (answered by jim_thompson5910)
log5(x-1)=4+log5(x-2) (answered by nerdybill)