Question

If f(x) = 5x, what is f–1(x)?

Answer 1

Answer:

$f^{-1} (x)=\frac{1}{5}x$

Step-by-step explanation:

we have

$f(x)=5x$

Let

y=f(x)

$y=5x$

Exchange the variables x for y and y for x

$x=5y$

isolate the variable y

$y=x/5$

Let

$f^{-1} (x)=y$

$f^{-1} (x)=\frac{1}{5}x$

Answer 2

Answer:

Option c

Step-by-step explanation:

Give that f(x) = 5x

We have to choose among the four options which is the inverse of f

Let us try directly from f(x)

$f(x) = 5xy =5x$

Divide both sides by 5

$x = \frac{y}{5} Verify:Let us do composiition of function as\\[tex]f(f^{-1} (x))=f(\frac{1}{5}x)\\ =5(\frac{1}{5}x)\\\\=x$=\frac{1}{5} x[/tex]

WE find that our answer is right