AP EAMCET202120 Aug 2021Evening ShiftMathematicsFunctionsActual
Let f x = x + 2 2 - 2 , x ≥ - 2 . Then f - 1 x =
Options
- A- 2 + x - 2
- B2 + x + 2
- C2 + x - 2
- D- 2 + x + 2
Correct answer
C. 2 + x - 2
Step-by-step solution
Let f x = x + 2 2 - 2 , x ≥ - 2 . Putting y = x + 2 2 - 2 y = x 2 + 4 x + 4 - 2 y = x 2 + 4 x + 2 x 2 + 4 x + 2 - y = 0 a = 1 ,   b = 4 ,   c = 2 - y x = - 4 ± 4 2 - 4 × 1 × 2 - y 2 × 1 x = - 4 ± 16 - 8 + 4 y 2 × 1 Then, x = - 2 + 2 + y , x ≥ - 2 Hence, f - 1 x = 2 + x - 2