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First, consider the ellipse $x^2 + 4y^2 \le 4$, which can be written as $\frac{x^2}{4} + y^2 \le 1$. This is an ellipse centered at the origin with semi-major axis $a=2$ and semi-minor axis $b=1$.
The area of the ellipse is $A_{ellipse} = \pi ab = \pi(2)(1) = 2\pi$.
Next, consider the inequalities $y \le |x| - 1$ and $y \ge 1 - |x|$. These represent the region between the lines $y = |x| - 1$ and $y = 1 - |x|$.
We need to find the area enclosed by the ellipse and these two inequalities. The lines $y = |x| - 1$ and $y = 1 - |x|$ intersect the ellipse.
Let's find the intersection points of $y = |x| - 1$ and the ellipse. Substituting $y = |x| - 1$ into the ellipse equation: $x^2 + 4(|x| - 1)^2 = 4$.
The intersection points are $(0, 1)$, $(\frac{8}{5}, -\frac{3}{5})$, and $(-\frac{8}{5}, -\frac{3}{5})$.
The required area is the area of the ellipse between $y = |x| - 1$ and $y = 1 - |x|$. Due to symmetry, we can consider the area in the first quadrant and multiply by 2.
In the first quadrant, we have $y = x - 1$ and $y = 1 - x$. The area is given by $2 \int_{0}^{\frac{8}{5}} [(1-x) - (x-1)] dx = 4 \int_{0}^{\frac{8}{5}} (1-x) dx$ from x=0 to 8/5. However, this is incorrect.
Let $x = 2\cos\theta$ and $y = \sin\theta$. Then $y = |x| - 1$ becomes $\sin\theta = |2\cos\theta| - 1$.
When $x > 0$, $\sin\theta = 2\cos\theta - 1$. When $x < 0$, $\sin\theta = -2\cos\theta - 1$.
Also, $y = 1 - |x|$ becomes $\sin\theta = 1 - |2\cos\theta|$.
When $x > 0$, $\sin\theta = 1 - 2\cos\theta$. When $x < 0$, $\sin\theta = 1 + 2\cos\theta$.
Consider the region in the first quadrant. The area is given by $\int_{0}^{8/5} (1-x - (x-1)) dx = \int_{0}^{8/5} (2-2x) dx = [2x - x^2]_{0}^{8/5} = 2(\frac{8}{5}) - (\frac{8}{5})^2 = \frac{16}{5} - \frac{64}{25} = \frac{80-64}{25} = \frac{16}{25}$.
The total area is $4 \times \frac{1}{2} \times base \times height = 4 \times \frac{1}{2} \times \frac{8}{5} \times \frac{3}{5} = \frac{48}{25}$.
Let $x = 2\cos\theta$ and $y = \sin\theta$. Then $\sin\theta = \frac{3}{5}$, so $\theta = \sin^{-1}(\frac{3}{5})$.
The area is $4(\frac{1}{2}ab(\theta - \sin\theta\cos\theta)) = 4(\frac{1}{2}(2)(1)(\sin^{-1}(\frac{3}{5}) - \frac{3}{5}\frac{4}{5})) = 4(\sin^{-1}(\frac{3}{5}) - \frac{12}{25}) = 4\sin^{-1}(\frac{3}{5}) - \frac{48}{25}$.
The area of the triangle is $2 \times \frac{1}{2} \times \frac{8}{5} \times \frac{3}{5} = \frac{24}{25}$.
The required area is $4\sin^{-1}(\frac{3}{5}) - \frac{24}{25} = 4\sin^{-1}(\frac{3}{5}) - \frac{6}{5}$.
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Pedagogical Audit
Bloom's Analysis:
This is an APPLY question because the student needs to apply their understanding of inequalities, area under curves, and trigonometric functions to solve the problem. They must combine these concepts to find the area enclosed by the given curves.
Knowledge Dimension:CONCEPTUAL
Justification:The question requires understanding the concepts of area calculation, inequalities, and the properties of ellipses and absolute value functions. It's not just about recalling formulas but applying them in a combined manner.
Syllabus Audit:
In the context of JEE, this is classified as COMPETENCY. The question requires the student to apply their knowledge of coordinate geometry and calculus to solve a problem that is not directly from the textbook. It tests the ability to combine different concepts.