SOLUTION: find the domain of the given functions: 1) f(x)=ln(x-3) 2) f(x)=(1/4)ln x

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Question 37290: find the domain of the given functions:
1) f(x)=ln(x-3)
2) f(x)=(1/4)ln x

Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Domain means "all allowable values of x." For
f(x) = ln(x - 3)
we know that we cannot take the log of non-positive numbers. Thus the argument of the log function must be greater than zero.
So x - 3 > 0 and x > 3
Thus the domain is the set of all x such that x is greater than 3, or
{x: x > 3}
Now for
f(x) = (1/4)ln x
we simply know x must be greater than zero, and
{x: x > 0}