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If f(x) = 5x, what is f^-1(x)?


Need help pls

If f(x) = 5x, what is f^-1(x)? Need help pls-example-1
User Litz
by
2.7k points

2 Answers

25 votes
25 votes

Writing a function in its inverse form

Answer:


f^(-1)(x) = (1)/(5)x\\

Explanation:

Given:


f(x) = 5x

Let
y = f(x) so we'll have the equation,
y = 5x. We then write it in its inverse form where we switch the
x and
y. The equation will be
x = 5y. Now we can solve for inverse
y.


x = 5y \\ 5y = x \\ 5y * (1)/(5) = x * (1)/(5) \\ y = (1)/(5)x

Since
y is
f(x), the inverse of
y should be the inverse of
f(x) or it is
f^(-1)(x)

We can then substitute inverse
y with
f^(-1)(x)

User Ian Evans
by
3.0k points
11 votes
11 votes

Answer:

f^-1(x) =1/5x

Explanation:

For Inverse graphs, you interchange the x-values and the y-values.

Y=5x

Inverse:

x=5y (interchange x and y)

Change the values again, you'll get something like this -5y=-x

Divide both sides of the equation by -5

You'll get y = -x/-5

Using laws of exponents x/5 can be written as 1/5x

So y=1/5x

User Jolindbe
by
3.1k points