Question 767173
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You started out ok.  The argument of the log function must be strictly greater than zero.


But consider just your numerator:  *[tex \LARGE x^2\ >\ 0\ \forall\ x\ \not =\ 0].  So far, we have to exclude 0.


But the denominator is positive so long as *[tex \LARGE x\ >\ 4], a restriction that includes *[tex \LARGE x\ \not =\ 0]


Hence the domain is *[tex \LARGE \left\{x\ \in\ \mathbb{R}\ :\ x\ >\ 4\right\}]


Note the strictly greater than relationship because the value 4 itself must be excluded to avoid division by zero.


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
<font face="Math1" size="+2">Egw to Beta kai to Sigma</font>
My calculator said it, I believe it, that settles it
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