99 Percentile Qs Bank for JEE MainMathematicsFunctions
If f(x)= 1 x+2 2 x-4 + 1 x-2 2 x-4 for x>2 , then f(11) is equal to
Options
- A7 6
- B5 6
- C6 7
- D5 7
Correct answer
C. 6 7
Step-by-step solution
We have, f(x)= 1 x+2 2 x-4 + 1 x-2 2 x-4 f(11)= 1 11+2 18 + 1 11-2 18 = 1 11+6 2 + 1 11-6 2 = 1 9+2+6 2 + 1 9+2-6 2 = 1 (3+ 2 )^2 + 1 (3- 2 )^2 = 1 3+ 2 + 1 3- 2 = 3- 2 +3+ 2 9-2 = 6 7