Math Problem Statement
Answer the questions about the following function. f left parenthesis x right parenthesis equals 3 x squared minus x minus 2 (a) Is the point left parenthesis 2 comma 8 right parenthesis on the graph of f? (b) If x = negative 1, what is f(x)? What point is on the graph of f? (c) If f(x) = negative 2, what is x? What point(s) are on the graph of f? (d) What is the domain of f? (e) List the x-intercept(s), if any, of the graph of f. (f) List the y-intercept, if there is one, of the graph of f.
Solution
Given the function , let's answer each question step by step:
(a) Is the point on the graph of ?
To check if the point is on the graph, we need to evaluate and see if the result equals 8.
Since , the point is indeed on the graph of .
(b) If , what is ? What point is on the graph of ?
We need to calculate :
So, , which means the point is on the graph of .
(c) If , what is ? What point(s) are on the graph of ?
We solve for when :
Add 2 to both sides:
Factor the equation:
So, or , which gives .
Thus, the points and are on the graph of .
(d) What is the domain of ?
The function is a polynomial, and polynomials are defined for all real numbers. Therefore, the domain of is:
(e) List the -intercept(s), if any, of the graph of .
The -intercepts occur when :
We solve this quadratic equation using the quadratic formula:
This gives two solutions:
Therefore, the -intercepts are and .
(f) List the -intercept, if there is one, of the graph of .
The -intercept occurs when :
So, the -intercept is .
Do you want more details on any step? Here are five related questions you might want to explore:
- What is the vertex of the function ?
- How would you find the axis of symmetry for this quadratic function?
- What is the range of the function ?
- Can you sketch the graph of the function using the points we found?
- What is the behavior of as and ?
Tip: For quadratic functions, the vertex can be found using the formula , where and come from the standard form .
Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Algebra
Quadratic Functions
Graphing
Domain and Range
Formulas
Quadratic formula: x = (-b ± √(b² - 4ac)) / 2a
Standard form of quadratic: f(x) = ax² + bx + c
Theorems
Quadratic Formula Theorem
Intercepts of Functions
Suitable Grade Level
Grades 9-11