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The area of the region bounded by the curves y=xy = x and y=x3y = x^3 is:

Solution

✅ Correct Option: 3

The curves intersect where they have the same value:

x=x3x = x^3

x−x3=0x - x^3 = 0

x(1−x2)=0x(1 - x^2) = 0

x(1−x)(1+x)=0x(1-x)(1+x) = 0

The curves intersect at x=−1,0,1x = -1, 0, 1


For the region from x=−1x = -1 to x=0x = 0:

Testing x=−0.5x = -0.5:

  • y=xy = x gives −0.5-0.5
  • y=x3y = x^3 gives −0.125-0.125

Since −0.125>−0.5-0.125 > -0.5, the curve y=x3y = x^3 is above y=xy = x in this region.

For the region from x=0x = 0 to x=1x = 1:

Testing x=0.5x = 0.5:

  • y=xy = x gives 0.50.5
  • y=x3y = x^3 gives 0.1250.125

Since 0.5>0.1250.5 > 0.125, the curve y=xy = x is above y=x3y = x^3 in this region.


The total area is:

Total Area=∫−10(x3−x) dx+∫01(x−x3) dx\text{Total Area} = \int_{-1}^{0} (x^3 - x)\,dx + \int_{0}^{1} (x - x^3)\,dx

For the first integral:

∫−10(x3−x) dx=[x44−x22]−10\int_{-1}^{0} (x^3 - x)\,dx = \left[\frac{x^4}{4} - \frac{x^2}{2}\right]_{-1}^{0}

=(0−0)−(14−12)= \left(0 - 0\right) - \left(\frac{1}{4} - \frac{1}{2}\right)

=0−(−14)= 0 - \left(-\frac{1}{4}\right)

=14= \frac{1}{4}

For the second integral:

∫01(x−x3) dx=[x22−x44]01\int_{0}^{1} (x - x^3)\,dx = \left[\frac{x^2}{2} - \frac{x^4}{4}\right]_{0}^{1}

=(12−14)−(0−0)= \left(\frac{1}{2} - \frac{1}{4}\right) - (0 - 0)

=14= \frac{1}{4}


Total Area =14+14= \frac{1}{4} + \frac{1}{4}

=12= \frac{1}{2} square units

Therefore, the area of the region bounded by the curves is 12\frac{1}{2} square units.

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