Math Problem Statement

Test 1- Functions.pdf

1017.07 KB

Solution

I see that you've uploaded a file that contains a set of mathematics questions. Based on the content, it appears to involve functions, including finding inverses, completing squares, determining domains and ranges, graphing, and understanding transformations.

Here’s a breakdown of the steps based on your request:

  1. State the domain of the function in its natural state without the restriction on the domain: The function f(x)=x26x16f(x) = x^2 - 6x - 16 is a quadratic function, and its domain without restriction is all real numbers, i.e., (,)(-\infty, \infty).

  2. Why is it necessary to restrict the domain when finding the inverse?: Quadratic functions are not one-to-one, meaning they fail the horizontal line test, so their inverses cannot be obtained unless we restrict the domain. Typically, we restrict the domain to x3x \geq 3 (since that part of the parabola is increasing, making the function one-to-one).

  3. Rewriting the function by completing the square: To complete the square for the function f(x)=x26x16f(x) = x^2 - 6x - 16, we can follow these steps:

    • Start by factoring the quadratic expression x26xx^2 - 6x.
    • To complete the square, take half of 6-6 (which is 3-3), and square it to get 99.
    • Rewrite the expression as f(x)=(x26x+9)916=(x3)225f(x) = (x^2 - 6x + 9) - 9 - 16 = (x - 3)^2 - 25.
  4. Finding the inverse function: The inverse of the function f(x)=(x3)225f(x) = (x - 3)^2 - 25 involves swapping xx and yy and solving for yy:

    • Start with x=(y3)225x = (y - 3)^2 - 25.
    • Add 25 to both sides: x+25=(y3)2x + 25 = (y - 3)^2.
    • Take the square root of both sides: y3=±x+25y - 3 = \pm \sqrt{x + 25}.
    • Since we restricted the domain to x3x \geq 3, we take the positive root: y=3+x+25y = 3 + \sqrt{x + 25}.
  5. Domain and range of f(x)f(x):

    • Domain of f(x)f(x) (with restriction x3x \geq 3): [3,)[3, \infty).
    • Range of f(x)f(x) (since the function opens upwards): [25,)[-25, \infty).

Would you like me to assist with other specific parts of this set of questions or explain any concepts in more detail?

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Functions
Quadratic Equations
Completing the Square
Inverse Functions
Domain and Range
Graphing

Formulas

f(x) = x^2 - 6x - 16
Inverse Function Formula
Domain and Range formulas

Theorems

Horizontal Line Test for Inverses
Completing the Square Theorem

Suitable Grade Level

Grades 9-11