JEE Main20198 Apr 2019Morning ShiftMathematicsLimitsActual
l i m x → 0 s i n 2 x 2 - 1 + c o s x equals
Options
- A4 2
- B2 2
- C2
- D4
Correct answer
A. 4 2
Step-by-step solution
l i m x → 0   s i n 2 x 2 - 1 + c o s x On Rationalisation, we get, = l i m x → 0   s i n 2 x 2 - 1 + c o s x × 2 + 1 + c o sx 2 + 1 + c o sx = l i m x → 0   2 sin x 2 cos x 2 2 1 - c o s x × 2 + 1 + cos x = l i m x → 0   4 s i n 2 x 2 c o s 2 x 2 2 s i n 2 x 2 × 2 + 1 + cos x = l i m x → 0   2 c o s 2 x 2 2 + 1 + c o s x = 2 × 2 2 = 4 2 .