Question 365515
 f(x)=log(7-x)
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Domain describes all values of x which makes sense for the function.
Since you can't take a log of 0 or a negative number:
7-x > 0
-x > -7
x < 7  (this is your domain)
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They may want to put it in the form of interval notation:
(-oo, 7)
where -oo indicates "negative infinity"