If α is the area of the common region that lies inside both the given ellipses, then the value of cotα is ____.
Answer: 0.75
Solution
The common region is symmetric. Computing the area in the first quadrant and multiplying by 8: α=8∫01/5(21−x2−x)dx. Evaluating the integral using standard formulas, we find α=2sin−1(51). Since sin−1(51)=tan−1(21), we have α=2tan−1(21)=tan−1(34) (using double angle formula). Thus cotα=43=0.75.
JEE Advanced · 2026 · 17 May 2026 · Paper 2 · Numerical answer