The inverse of a function is given by f^{-1} : x → x+1/4.

Correct Answer is : f:x→4x−1f : x → 4x - 1f:x→4x−1

Correct Answer is : f:x→4x−1f : x → 4x - 1f:x→4x−1

Test Index

WAEC Further Mathematics 2011 Paper

Question : 17

Total: 40

f^{-1} : x \to \frac{x+1}{4}

Solution:

Concept:

The function

f

is the inverse of the given function

f^{-1}

. So, find the inverse of

f^{-1}

by swapping the roles of

x

and

y

Explanation:

Let

y = f^{-1}(x)

. Since

f^{-1}(x) = \frac{x+1}{4}

, we write:

y = \frac{x+1}{4}

To find the inverse, interchange

x

and

y

x = \frac{y+1}{4}

Multiply both sides by

4

4x = y + 1

Subtract

1

from both sides:

y = 4x - 1

Since

y = f(x)

, we get:

f(x) = 4x - 1

Thus, the function is

f : x \to 4x - 1

Answer:

f : x \to 4x - 1

Go to Question:

Prev Question

Next Question