Question 548071: how to solve: ln(x+5)=ln(x-1)-ln(x+1)
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! how to solve: ln(x+5)=ln(x-1)-ln(x+1)
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ln(x+5)=ln(x-1)-ln(x+1)
ln(x+5)-ln(x-1)+ln(x+1)=0
place under single log
ln[(x+5)(x+1)/(x-1)]=0
convert to exponential form: base(e) raised to log of number(0)=number[(x+5)(x+1)/(x-1)]
e^0=(x+5)(x+1)/(x-1)=1
(x+5)(x+1)=(x-1)
x^2+6x+5=x-1
x^2+5x+6=0
(x+3)(x+2)=0
x=-3 (reject, (x+1)>0)
or
x=-2 (reject, (x+1)>0)
ans: no solution
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