COMEDK2025MathematicsLimitsActual
_ x 4 ^2 x-2 x-1 =
Options
- A1
- B2
- C1 2
- D2
Correct answer
D. 2
Step-by-step solution
Given the limit L = _ x 4 ^2 x-2 x-1 . Using the identity ^2 x = 1 + ^2 x , the expression becomes: L = _ x 4 1 + ^2 x - 2 x - 1 L = _ x 4 ^2 x - 1 x - 1 Factoring the numerator as a difference of squares: L = _ x 4 ( x - 1)( x + 1) x - 1 Canceling the common term ( x - 1) for x 4 : L = _ x 4 ( x + 1) Substituting x = 4 : L = ( 4 ) + 1 = 1 + 1 = 2 . Answer: 2