Solution
Related Formula
A function is non-differentiable at sharp corner transition points where left-hand and right-hand derivatives do not match.
Core Logic
Analyze the behavior of powers of x across significant transition domains: For x < -1: x is the largest because higher odd powers of negative fractions decrease rapidly (x > x³ > x⁵...). For -1 ≤ x < 0: x²¹ is largest (closest to zero from below). For 0 ≤ x < 1: x is largest. For x ≥ 1: x²¹ is largest.
f(x) = cases x, & x < -1 x²¹, & -1 ≤ x < 0 x, & 0 ≤ x < 1 x²¹, & x ≥ 1 casesStep 1: Continuity and Differentiability Checks
At critical intersection boundaries x = -1, 0, 1, f(x) matches continuous values perfectly, so n = 0. Now check derivative transitions f'(x):
f'(x) = cases 1, & x < -1 21x²⁰, & -1 < x < 0 1, & 0 < x < 1 21x²⁰, & x > 1 casesAt x = -1: LHD = 1, RHD = 21(-1)²⁰ = 21 Non-differentiable. At x = 0: LHD = 0, RHD = 1 Non-differentiable. At x = 1: LHD = 1, RHD = 21(1)²⁰ = 21 Non-differentiable.
Step 2: Conclusion
Thus, the function is non-differentiable at exactly 3 points (x = -1, 0, 1), so m = 3. Since n = 0:
m + n = 3 + 0 = 3Pattern Recognition
Maximum boundary tracking curves for standard power elements always form continuous shapes but introduce non-differentiable sharp corners at every intersection crossover point.
Chapter Mix
Class 12 Mathematics: Limits, Continuity and Differentiability