Math Problem Statement
Question content area top Part 1 Find all rational zeros of f. Then (if necessary) use the depressed equation to find all roots of the equation f(x)equals0. f(x)equalsxcubednegative 37xplus 6 Question content area bottom Part 1 Select the correct choice below and fill in the answer box within your choice. A. The set of all zeros of the given function is StartSet nothing EndSet . (Simplify your answer. Type an exact answer, using radicals as needed. Use a comma to separate answers as needed.) B. There are no real zeros.
Solution
We are given the cubic function , and we are tasked with finding all rational zeros, then solving for all roots of the equation .
Step 1: Rational Root Theorem
The Rational Root Theorem helps to identify possible rational roots of a polynomial. It states that any rational root, written as , must satisfy:
- is a factor of the constant term (in this case, 6),
- is a factor of the leading coefficient (in this case, 1).
For , the constant term is 6, and the leading coefficient is 1. The possible rational roots are the factors of 6 divided by the factors of 1. Thus, the possible rational roots are:
Step 2: Testing Possible Rational Roots
We now test each of the possible rational roots using synthetic division or substitution into .
Testing :
Testing :
Testing :
Testing :
Testing :
Testing :
Testing :
So, is a root.
Step 3: Depressed Equation
Now that we know is a root, we can factor from the polynomial. To do this, we perform synthetic division on by .
Performing synthetic division:
6 & 1 & 0 & -37 & 6 \\ & & 6 & 36 & -6 \\ \hline & 1 & 6 & -1 & 0 \\ \end{array}$$ The quotient is $$x^2 + 6x - 1$$. So, we can write: $$f(x) = (x - 6)(x^2 + 6x - 1)$$ ### Step 4: Solving the Quadratic Equation Next, solve $$x^2 + 6x - 1 = 0$$ using the quadratic formula: $$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ For $$x^2 + 6x - 1 = 0$$, we have $$a = 1$$, $$b = 6$$, and $$c = -1$$. Substituting into the quadratic formula: $$x = \frac{-6 \pm \sqrt{6^2 - 4(1)(-1)}}{2(1)} = \frac{-6 \pm \sqrt{36 + 4}}{2} = \frac{-6 \pm \sqrt{40}}{2} = \frac{-6 \pm 2\sqrt{10}}{2}$$ $$x = -3 \pm \sqrt{10}$$ ### Step 5: Final Answer Thus, the three roots of the equation are: $$x = 6, \quad x = -3 + \sqrt{10}, \quad x = -3 - \sqrt{10}$$ ### Final Answer: The set of all zeros is: $$\{6, -3 + \sqrt{10}, -3 - \sqrt{10}\}$$ Would you like further details or explanations? --- Here are some related questions to deepen understanding: 1. What are the conditions for using the Rational Root Theorem? 2. How does synthetic division help in factoring polynomials? 3. What is the significance of a "depressed equation" in solving polynomials? 4. How can you verify that the solutions to the quadratic are correct? 5. What are the differences between rational and irrational roots? **Tip:** Always verify potential roots by substituting them back into the original equation to avoid calculation errors.Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Algebra
Cubic Polynomials
Synthetic Division
Quadratic Equations
Formulas
Rational Root Theorem
Quadratic Formula: x = (-b ± √(b^2 - 4ac)) / 2a
Theorems
Rational Root Theorem
Suitable Grade Level
Grades 10-12
Related Recommendation
Find All Zeros of the Cubic Function x^3 + 9x^2 + 31x + 39
Find Rational Zeros of the Polynomial f(x) = x^3 - x^2 - 37x - 35
Find All Zeros of the Cubic Polynomial f(x) = 3x^3 - 2x^2 - 42x - 27
Solving the Cubic Polynomial Equation x^3 - 3x^2 - 4x - 12 = 0
Rational Zeros Theorem for f(x) = 3x^3 - 3x^2 - 4x + 5