ExamBro
ExamBro
JEE Mains · Maths · STD 12 - 5. continuity and differentiation

If \([t]\) denotes the greatest integer \(\leq t\), then number of points, at which the function \(f ( x )=4|2 x +3|+\) \(9\left[x+\frac{1}{2}\right]-12[x+20]\) is not differentiable in the open interval \((-20,20)\), is\(.....\)

  1. A \(78\)
  2. B \(79\)
  3. C \(80\)
  4. D \(81\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(79\)

Step-by-step Solution

Detailed explanation

\(f(x)=4|2 x+3|+9\left[x+\frac{1}{2}\right]-12[x+20]\) \(x \in(-20,20)\) \(f ( x )\) is not Diff. at \(x = I \in\{-19,-18, \ldots .0, \ldots 19\}=39\) at \(x = I +\frac{1}{2}, f ( x )\) Non diff. at 39 points Check at \(x =\frac{-3}{2}\) Discount at…
Same subject
Explore more questions on app