99 Percentile Qs Bank for JEE MainMathematicsBasics of Mathematics
Set of all real values of x satisfying the in equation log 2 x 2 − 5 x + 4 log 2 x 2 + 1 > 1 is
Options
- A- ∞ , 3 5 - 0
- B- ∞ , 1 - 0
- C3 5 , ∞
- D4 , ∞
Correct answer
A. - ∞ , 3 5 - 0
Step-by-step solution
Here, it is given that log 2 x 2 − 5 x + 4 log 2 x 2 + 1 > 1 x 2 − 5 x + 4 > 0 ⇒ x − 4 x − 1 > 0 ⇒ x ∈ − ∞ , 1 ∪ 4 , ∞                 . . . 1 x 2 + 1 > 0 which is true ∀ x ∈ R                   . . . 2 log 2 x 2 − 5 x + 4 > log 2 x 2 + 1 x 2 − 5 x + 4 > x 2 + 1 − 5 x + 3 > 0 x < 3 5       &