The equation of a curve is given by y=f(x) wheref′(x) is a continuous function. The tangent at points(1, f(1)) , (2,f(2)) and (3,f(3)) make angles π6,π3and π4 respectively with positive x-axis. Then∫23 f′(x)f′′(x)dx+∫13 f′′(x)dx is