Mathematics · Area under the Curves

JEE Main 2025 — 2 April, Morning Shift — Question 43

If the area of the region {(x,y):∣4−x2∣≤y≤x2, y≤4, x≥0}\{(x,y): |4 - x^2| \le y \le x^2, \, y \le 4, \, x \ge 0\} is 802α−β80\sqrt{2}\alpha - \beta, where α,β∈N\alpha, \beta \in \mathbb{N}, then α+β\alpha + \beta is equal to

Answer: 22

Numerical answer — enter this value.

Step-by-step solution

Area= ∫22(x2−(4−x2))dx+(22−2)×4−∫222(x2−4)dx\int_{\sqrt{2}}^{2}\left(x^{2}-\left(4-x^{2}\right)\right) d x+(2 \sqrt{2}-2) \times 4-\int_{2}^{2 \sqrt{2}}\left(x^{2}-4\right) d x

=[2x33−4x]22+82−8−[x33−4x]222=\left[\frac{2 x^{3}}{3}-4 x\right]_{\sqrt{2}}^{2}+8 \sqrt{2}-8-\left[\frac{x^{3}}{3}-4 x\right]_{2}^{2 \sqrt{2}}

=4023−16=\frac{40 \sqrt{2}}{3}-16

⇒α=6,β=16⇒α+β=22\Rightarrow \alpha=6, \beta=16 \Rightarrow \alpha+\beta=22

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Subject
Mathematics
Chapter
Area under the Curves
Topic
Area under the Curves