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William
10-28-2013, 05:43 PM
Which of the following is the domain of the function f(x)=log_{x}(x^2-1)?


(A) x>0

(B) x>0 \ and \ x\neq 1

(C) x<-1 \ or \ x>1

(D) x>1

Thanks!

Thomas
10-28-2013, 05:44 PM
The base of a logarithm must be greater than zero and different than one.
x>0 \ and \ x\neq 1

The argument of a logarithm must be greater than zero.
x^2-1 >0 \Rightarrow (x-1)(x+1) >0 \Rightarrow x<-1 \ or \ x>1

Therefore the domain of the function f is:
[tex] x>1[tex]

Therefore the correct answer is (A).

William
10-28-2013, 05:45 PM
Thanks Thomas!!;)