How do you solve Ln(x+2)+ln(x-2)=3?

1 Answer
Mar 8, 2016

x~~4.9

Explanation:

ln(x+2)+ln(x-2)=3
ln[(x+2)(x-2)]=3-> use property log_bx+log_by=log_b(xy)
ln (x^2-4) =3
e^3=x^2-4-> use definition log_bx=n iffb^n=x
e^3+4=x^2-> solve for x
x=+-sqrt(e^3+4)
x~~4.9, x~~-4.9