Continuity and Differentiability · Class 12 · CBSE · Science Mathematics

Let f(x) = (x^2 - 4)/(x - 2) for x ≠ 2 and f(2) = k. For which value of k is f continuous at x = 2?

Practice question from Continuity and Differentiability (Class 12 · CBSE · Science Mathematics), with the correct answer and a step-by-step solution.

easy · MCQ · Q-ADE59F

Let f(x) = (x^2 - 4)/(x - 2) for x ≠ 2 and f(2) = k. For which value of k is f continuous at x = 2?

  1. A.0
  2. B.2
  3. C.4Correct answer
  4. D.Does not exist

Solution

For x≠2x \ne 2, f(x)=(x−2)(x+2)x−2=x+2f(x)=\frac{(x-2)(x+2)}{x-2}=x+2. Hence, lim⁡x→2f(x)=4\lim_{x\to 2}f(x)=4. Continuity at x=2x=2 requires f(2)=k=4f(2)=k=4.

More from Continuity and Differentiability

All of Continuity and Differentiability

Practise more Mathematics

Sign up free for adaptive practice on this chapter, with instant feedback and hints on every question.

Start practising free

Free to start · No credit card needed