Let \(A={(\alpha ,\beta )\in \mathrm{R}\times \mathrm{R}:|\alpha -1|\leq 4\text{ and }|\beta -5|\leq 6}\) and \(B=\left{…
Let \(A={(\alpha ,\beta )\in \mathrm{R}\times \mathrm{R}:|\alpha -1|\leq 4\text{ and }|\beta -5|\leq 6}\) and \(B=\left{(\alpha ,\beta )\in \mathrm{R}\times \mathrm{R}:16(\alpha -2{)}^{2}+9(\beta -6{)}^{2}\leq 144\right}\). Then
\(\mathrm{B}\subset \mathrm{A}\)
Set A:
\(A=\{(\alpha, \beta) \in \mathbb{R} \times \mathbb{R}:|\alpha-1| \leq 4\) and \(|\beta-5| \leq 6\}\)
This represents a rectangle with:
\(−3\leq \alpha \leq 5\) (from \(\alpha −1\in [−4,4]\))
\(−1\leq \beta \leq 11\) (from \(\beta −5\in [−6,6]\))
Set B:
\(B=\left\{(\alpha, \beta) \in \mathbb{R} \times \mathbb{R}: 16(\alpha-2)^2+9(\beta-6)^2 \leq 144\right\}\)
This is an ellipse centered at \((2,6)\).
Standard form: \(\frac{(\alpha-2)^2}{9}+\frac{(\beta-6)^2}{16} \leq 1\)
So, it has:
Horizontal semi-axis \(= 3\)
Vertical semi-axis \(= 4\)
Hence, the ellipse spans:
\(\alpha \in [2−3,2+3]=[−1,5]\)
\(\beta \in [6−4,6+4]=[2,10]\)
Now compare sets:
Rectangle A: \(\alpha \in [−3,5],\beta \in [−1,11]\)
Ellipse B: completely lies within bounds of A
So, B is a subset of A, but A is not a subset of B (e.g., point \((−3,−1)\) is in A but not in B)
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