NDA 2 2025 Maths, question 98

Topic: Integral calculus

Q98

What is the area of the region bounded by $|x|\le 2k$ and $|y|\le k$ , where $k$ is a positive real number?

(a) $2k^{2}$
(b) $4k^{2}$
(c) $5k^{2}$
(d) $8k^{2}$ Correct answer

Solution.

Answer: (d) $8k^{2}$

The inequalities describe a rectangle with x from −2k to 2k and y from −k to k.
Its side lengths are 4k and 2k, so the area is 8k².