CAT 1994QA Question 39

Composite FunctionsEasy
Passage / Data

Answer the next 4 questions based on the information given below:

If f (x) = 2x + 3 and g(x) =  x-32, then

What is the value of (gofofogogof)(x) × (fogofog)(x)?

Answer & solution

  • A

    x

  • x2

  • C

    5x+34x-1

  • D

    (x+3)(5x+3)(4x-5)(4x-1)

Solution

From Question 87, fog(x) = gof (x) = x, you will realise that if you were to form a chain of these functions for even number of times, you would still end up getting x.
For eg. fogofog(x) = fog(x) = x. Since both the brackets have the functions repeated for even number of times, each of their value will be x and their product will be x2.

CAT 1994 QA Q39: What is the value of (gofofogogof)(x) × (fogofog)(x)? — Solution | TheCATExam