Given equations are:
x = 3 ...... (1)
And y2 = 4x ...... (2)
Equation (1) represents a line parallel to the y - axis at a distance of 3 units and equation (2) represents a parabola with vertex at origin and x - axis as its axis; A rough sketch is given as below:
We have to find the area of shaded region.
Required area
= shaded region OBCAO
= 2 (shaded region OBCO) (as it is symmetrical about the x - axis)
(the area can be found by taking a small slice in each region of width Δx, then the area of that sliced part will be yΔx as it is a rectangle and then integrating it to get the area of the whole region)
\(=2\int^3_0 y\,dx\) (As x is between (0,3) and the value of y varies)
On integrating we get,
On applying the limits, we get,
Hence the area of the region bounded between the line x = 3 and the parabola y2 = 4x is equal to \(8\sqrt{3}\) square units.