Engineering
Mathematics
Important Points on Derivability
Question

Let f(x) = 2 + | x – 1 | and g(x) = min. (f(t)) where 1≤t≤x∀x∈[1,∞) and number of points of non‑derivability of g(x) in [1,∞) be m.

If h(x) = x | x2 – 3x | e| x – 3 | + [3+sgn (x2−1−5x)4+x2]+{13+[x2−2x3|x|+1]} is discontinuous at n number of points then find (m + n).

[Note: [z] & {z} denotes greatest integer function less than or equal & fractional part function of z.]

JEE Advance
College PredictorLive

Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.

Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA

Solution

Clearly, f(t) ={3−t,t<1t+1,t≥1

∴ g(x) = 2∀x≥1

∴ Number of points of non‑derivability = 0.

and h(x) = x | x | | x – 3 | e| x – 3 | + 0 + 13always continuous.

∴ m + n = 0.