Question
What is the derivative of x |x| with respect to x, where x<0 ?
NDA
Mathematics
Continuity and Differentiability
2026
NDA 2026 (Phase 1)
NDA Mathematics Question (2026) — Solution
Options
- A. -1
- B. 0
- C. 1
- D. x
Answer
B. 0
Step-by-step solution
Given function is f(x) = x |x| . For x Substituting this into the function gives f(x) = x -x = -1. Differentiating with respect to x gives d dx (-1) = 0. Answer: 0
Related: Mathematics — Continuity and Differentiability · All PYQ Banks