For ƒ(x) = x 2 – 2 |x|, test the continuity and differentiability of g(x) in the interval [–2, 3], where
g (x) =
, are -
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Here ƒ(x) = 
Case 1 : –2 ≤ x < –1, ƒ(x) decreases ⇒ g (x) = x 2 + 2x
Case 2 : –1 ≤ x < 0, ƒ(x) increases ⇒ g (x) = –1
Case 3 : 0 ≤ x < 1, ƒ(x) decreases ⇒ g(x) = 0
Case 4 : 1 ≤ x < 2, ƒ(x) increases but ƒ(x) < 0
⇒ g (x) = ƒ(0) = 0
Case 5 : 2 ≤ x ≤ 3, ƒ(x) increases and ƒ(x) ≥ 0
∀ x ∈ [2, 3)
⇒ g (x) = ƒ (x) = x 2 – 2x, 2 ≤ x ≤ 3

Therefore g (x) = 
Clearly g (x) is continuous everywhere except at x = 0.
Also g (x) is non differentiable at x = 0 and 2.
Hence is the correct answer.
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