Question 379445
The domain of a function are all allowable values for x.
The only values of x that WOULDN'T be allowed here are those which make the denominator go to zero...so we set it equal to zero and solve it...
So
{{{x^2 - 10x + 21 = 0}}}
{{{(x - 7)(x - 3) = 0}}}
{{{x = 7 or x = 3}}}
Thus the domain is all real numbers except x cannot be 3 or 7.