Question

The area of the region (in square units) bounded by the curve x² = 4y, line x = 2 and x-axis is

Options

• 1

• 2/3

• 4/3

• 8/3

Answer 1

2/3

Point of intersection of the parabola x² = 4y and straight line x = 2 is given by
\[x^2 = 4y\text{ and }x = 2\]
\[ \Rightarrow 4 = 4y\]
\[ \Rightarrow y = 1\]
\[A\left( 2, 1 \right)\text{ is the point of intersection of the curve and straight line }\]
\[\text{ Area of shaded region OAB }= \int_0^2 y dx\]
\[ = \int_0^2 \frac{x^2}{4} dx \]
\[ = \left[ \frac{x^3}{12} \right]_0^2 \]
\[ = \frac{2^3}{12} - 0\]
\[ = \frac{2}{3}\text{ square units }\]