The integer '', for which the inequality is valid for every in , is :
- (A)4
- (B)3✓ Correct
- (C)0
- (D)2
Answer: (B)
Solution
The quadratic has a positive leading coefficient, so it stays positive for every real exactly when its discriminant is negative:
Expanding, , that is , so and . The only integer in this interval is .
Expanding, , that is , so and . The only integer in this interval is .
JEE Main · 2021 · 25 Feb 2021 · Shift 1 · Single correct option