The position vector of the point of inersection of the medians of a triangle, whose vertices are $$A(1,2,3), B(1,0,3)$$ and $$C(4,1,-3)$$ is

$$\int\limits_{ - \pi }^\pi {{{x\sin x} \over {1 + {{\cos }^2}x}}dx = } $$

$$\int {{e^x}\left( {{{x - 1} \over {{x^2}}}} \right)dx = } $$

Area of the triangle formed by the lines $$y^2-9 x y+18 x^2=0$$ and $$y=9$$ is