Answer
$f(x) = (x-1/2)^2 - 25/4$
See graph below.
Work Step by Step
The standard form is $a(x-h)^2 + k$
Given $f(x) = x^2 - x - 6$
Complete the square to convert f(x) to standard form and graph it.
$f(x) = x^2 - x + 1/4 - 6 - 1/4$
$f(x) = (x-1/2)^2 - 25/4$
See graph below.