Question

Given the function: y = 4x - 1, find f-¹ (7)

Answer 1

Step 1

Given;

`y=4x-1`

Required; To find

`f^(-1)(7)`

Step 2

Find the inverse of f(x)

Set x =y and y =x

`x=4y-1`

solve for y

`\begin{gathered} 4y=x+1 \\ y=(x+1)/(4) \\ f^(-1)(x)=(x+1)/(4) \end{gathered}`
`\begin{gathered} Find\text{ f}^(-1)(7) \\ \text{ f}^(-1)(7)=(7+1)/(4)=(8)/(4)=2 \\ \text{ f}^(-1)(7)=2 \end{gathered}`

Answer;

`\text{ f}^(-1)(7)=2`