Concept:The integral is of the form ∫x2−ax+b1dx, which simplifies by completing the square and using the standard tan−1 formula.Explanation:Complete the square in the denominator:x2−5x+8=(x−25)2+47So the integral becomes:∫(x−25)2+(27)2dxUsing the standard formula:∫x2+a2dx=a1tan−1(ax)+cHere, a=27, so:72tan−1(27x−25)+cSimplify the argument:27x−25=72x−5Hence:∫x2−5x+81dx=72tan−1(72x−5)+cAnswer:Option C