Question:medium

The area of the shaded region bounded by the curves \( y^2 = x, x = 4 \) and the x-axis is given by:
The area of the shaded region bounded by the curves

Show Hint

To calculate the area between curves, integrate the function that represents the curve from the lower limit to the upper limit.
Updated On: Feb 25, 2026
  • \( \int_0^4 x \, dx \)
  • \( 2 \int_0^4 \sqrt{x} \, dx \)
  • \( 4 \int_0^4 \sqrt{x} \, dx \)
  • \( 4 \int_0^4 \frac{1}{\sqrt{x}} \, dx \)
Show Solution

The Correct Option is B

Solution and Explanation

We need to calculate the area of the region bounded by the curve \( y^2 = x \), the line \( x = 4 \), and the x-axis. The process is as follows: Step 1: Rewrite the curve equation.The given equation \( y^2 = x \) can be expressed as:\[y = \sqrt{x}.\]This equation represents the upper half of the parabola, as the square root function yields only non-negative values. Step 2: Formulate the integral for the area.To find the area under the curve, we integrate \( y = \sqrt{x} \) with respect to \( x \) from \( x = 0 \) to \( x = 4 \). The area between the curve and the x-axis is given by the integral:\[\text{Area} = \int_0^4 \sqrt{x} \, dx.\] Step 3: Account for symmetry.The problem requires the area of the region enclosed by \( y^2 = x \) and the x-axis. Since \( y^2 = x \) defines a parabola symmetric about the x-axis, there are two equal areas: one above the x-axis (\( y = \sqrt{x} \)) and one below (\( y = -\sqrt{x} \)). The total area is therefore twice the area calculated in Step 2.Thus, the total area is:\[\text{Total Area} = 2 \int_0^4 \sqrt{x} \, dx.\] Step 4: Evaluate the integral.The integral of \( \sqrt{x} \) is:\[\int \sqrt{x} \, dx = \int x^{1/2} \, dx = \frac{2}{3} x^{3/2}.\]Evaluating this definite integral from \( 0 \) to \( 4 \):\[\int_0^4 \sqrt{x} \, dx = \left[ \frac{2}{3} x^{3/2} \right]_0^4 = \frac{2}{3} \left( 4^{3/2} - 0^{3/2} \right).\]Given that \( 4^{3/2} = 8 \), we get:\[\int_0^4 \sqrt{x} \, dx = \frac{2}{3} \times 8 = \frac{16}{3}.\]Finally, the total area is:\[\text{Total Area} = 2 \times \frac{16}{3} = \frac{32}{3}.\]This confirms the total area is represented by \( 2 \int_0^4 \sqrt{x} \, dx \).\[\boxed{2 \int_0^4 \sqrt{x} \, dx}\]
Was this answer helpful?
0