Find the domain of the real-valued function:
`f(x)=(x^(2)-x+1)/(x^(2)-5x+4)`.

Explanation

We have, `f(x)=(x^(2)-x+1)/(x^(2)-5x+4)`
Clearly, f(x) is defined for all real values of x except those at which `x^(2)-5x+4=0`
But, `x^(2)-5x+4=0implies(x -1)(x-4)=0impliesx=1orx=4`.
`:."dom "(f)=R-{1,4}`.