What is the derivative of the inverse function when f(x) = x^1/3?

To find the derivative of the inverse function, we first need to clarify a few concepts regarding inverse functions and derivatives.

Let’s denote the function as f(x) = x^(1/3). To find the derivative of the inverse function, we can utilize the relationship between a function and its inverse, given by the formula:

(f-1(y))’ = 1 / f'(x)

where f'(x) is the derivative of the function f evaluated at the point x, and y = f(x).

First, we calculate the derivative of f(x):

f'(x) = (1/3)x^(-2/3)

Now we need to find the inverse function of f. To do that, we set y = f(x) = x^(1/3). To solve for x in terms of y, we cube both sides:

y^3 = x

Thus, the inverse function is:

f-1(y) = y^3

Next, we need to evaluate the derivative of the inverse function:

(f-1(y))’ = 1 / f'(x), where x = f-1(y) = y^3 means we need to substitute x = y^3 into the expression for the derivative:

f'(y^3) = (1/3)(y^3)^(-2/3) = (1/3)(y^(-2)) = y^(-2)/3 = 1 / (3y^2)

Finally, substituting this back into the inverse derivative gives:

(f-1(y))’ = 1 / f'(y^3) = 1 / (1 / (3y^2)) = 3y^2

Therefore, the derivative of the inverse function of f(x) = x^(1/3) is:

(f-1(y))’ = 3y^2

In summary, the derivative of the inverse function of f(x) = x^(1/3) can be expressed as:

(f-1(y))’ = 3f(x)^2 when properly translated back to relate to original function variables.

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