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Consider the function f(x)= x^2+10 for the domain [0, +infinity). find f^-1(x), where f^-1 is the inverse of fedit: PLEASE DOUBLE CHECK ANSWERS.

User Roger Wolf
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1 Answer

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Answer

The inverse of this function is given as

f⁻¹(x) = √(x - 10)

Domain in interval form = [10, ∞)

OR

Domain in inequality form = 10 ≤ x < ∞

Step-by-step explanation

First of, the inverse of a function is a function that reverses the actions of the function. That is, for the inverse function, if we are given f(x), we would be able to obtain x.

The step to finding a function's inverse is to write y instead of f(x). We then rewrite by replacing the y by x and then make y the subject of formula, the y which is a subject of formula now, represents the inverse function, f⁻¹(x).

f(x) = x² + 10

We will write y instead of f(x)

y = x² + 10

We then replace y by x

x = y² + 10

We will then make y the subject of formula

x = y² + 10

y² + 10 = x

y² = x - 10

Take the square root of both sides

√(y²) = √(x - 10)

y = √(x - 10)

f⁻¹(x) = √(x - 10)

For the domain of this inverse of this function, we know that there is no real solution for the square root of a negative number, we know that the domain of this function has to be values of x that make the expression under the square root equal to or greater than 0.

x - 10 ≥ 0

Add 10 to both sides

x - 10 + 10 ≥ 0 + 10

x ≥ 10

Domain = [10, ∞) OR 10 ≤ x < ∞

Hope this Helps!!!

User Jasenkoh
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