Using integration find the area of region bounded by the triangle whose vertices are (– 1, 0), (1, 3) and (3, 2).



BL and CM are drawn perpendicular to x – axis.


We can see that from the figure that,


Area(ΔACB) = Area(ALBA) + Area(BLMCA) - Area(AMCA) …(1)


Now, equation of line segment AB is




Thus, Area(ALBA) =



Now, equation of line segment BC is




Thus, Area (BLMCB) =



Now, equation of line segment AC is




Thus, Area (AMCA) =



Now putting all these values in equation (1), we get,


Area(ΔABC) = (3 + 5 – 4) = 4 units.


5
1