Math Problem Statement

Find the inverse for each of the following functions: f(x) = 11x + 9, s(x) = -15 / (x + 3), h(x) = 9x^3 + 9, r(x) = (5x + 7)^(1/3)

Solution

To find the inverse of each given function, we need to follow these general steps:

  1. Replace f(x)f(x), s(x)s(x), h(x)h(x), or r(x)r(x) with yy.
  2. Swap xx and yy in the equation.
  3. Solve for yy in terms of xx.
  4. Replace yy with f1(x)f^{-1}(x), s1(x)s^{-1}(x), h1(x)h^{-1}(x), or r1(x)r^{-1}(x) as required.

Let's go through each function individually.


1. f(x)=11x+9f(x) = 11x + 9

To find f1(x)f^{-1}(x):

  1. Write y=11x+9y = 11x + 9.
  2. Swap xx and yy: x=11y+9x = 11y + 9.
  3. Solve for yy: x9=11yx - 9 = 11y y=x911y = \frac{x - 9}{11}
  4. Thus, f1(x)=x911f^{-1}(x) = \frac{x - 9}{11}.

2. s(x)=15x+3s(x) = -\frac{15}{x + 3}

To find s1(x)s^{-1}(x):

  1. Write y=15x+3y = -\frac{15}{x + 3}.
  2. Swap xx and yy: x=15y+3x = -\frac{15}{y + 3}.
  3. Solve for yy: x=15y+3-x = \frac{15}{y + 3} x(y+3)=15-x(y + 3) = 15 xy3x=15-xy - 3x = 15 xy=15+3x-xy = 15 + 3x [

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Inverse Functions

Formulas

If f(x) = y, then f^(-1)(x) can be found by solving for y in terms of x
For rational functions, f(x) = a / (x + b) has an inverse that can be solved by cross-multiplying

Theorems

Inverse Function Theorem

Suitable Grade Level

Grades 10-12