AP EAMCET202120 Aug 2021Evening ShiftMathematicsFunctionsActual
If f : R → R and g : R → R are two functions defined by f x = a x + b a ≠ 0 ∀ x ∈ R and g x = c x 3 + d c ≠ 0 ∀ x ∈ R , then f o g - 1 x =
Options
- Ax - a d + b a c 1 2
- Bx + a d - b a c 1 3
- Cx - a d - b a c 1 3
- Dx + a d + b a c 1 3
Correct answer
C. x - a d - b a c 1 3
Step-by-step solution
Given, f x = a x + b and g x = c x 3 + d f o g x = f g x f o g x = a g x + b = a c x 3 + d + b Let, y = a c x 3 + a d + b x 3 = y - a d - b a c x = y - a d - b a c 1 3 Hence, f o g - 1 x = x - a d - b a c 1 3