Find the area of the region included between y2 = 9x and y = x
In y2 = 9x parabola it is not defined for negative values of x hence the parabola will be to the right of Y-axis passing through (0, 0)
And y = x is a straight line passing through origin
We have to find area between y2 = 9x and y = x shown below
To find intersection point of parabola and line solve parabola equation and line equation simultaneously
Put y = x in y2 = 9x
⇒ x2 = 9x
⇒ x = 9
Put x = 9 in y = x we get y = 9
Hence point of intersection is (9, 9)
⇒ area between parabola and line = area under parabola – area under line …(i)
Let us find area under parabola
⇒ y2 = 9x
⇒ y = 3√x
Integrate from 0 to 9
Now let us find area under straight line y = x
y = x
Integrate from 0 to 9
Using (i)
⇒ area between parabola and line = 54 – 40.5 = 13.5 unit2
Hence area bounded is 13.5 unit2