NTA Abhyas JEE Main2020MathematicsContinuity and DifferentiabilityPractice
If the function f x = 1 - x 2 tan π x 2 is continuous at x = 1 , then f 1 is equal to
Options
- A1 π
- Bπ 2
- C0
- Dπ
Correct answer
A. 1 π
Step-by-step solution
f 1 = l i m x → 1 f x = l i m x → 1 1 - x 2 tan π x 2 Put x = 1 + h = lim h → 0 1 - 1 + h 2 tan π 2 1 + h = lim h → 0 - h 2 tan π 2 + π h 2 = lim h → 0 - h 2 - cot π h 2 = l i m h → 0 π 2 ⋅ h tan π h 2 ⋅ 1 π = 1 π