Chapter 6: Problem 60
Solve. $$ 8 n^{3}+10 n^{2}+3 n=0 $$
Short Answer
Expert verified
The solutions are \( n = 0 \), \( n = -\frac{1}{2} \), and \( n = -\frac{3}{4} \).
Step by step solution
01
Factor Out Common Terms
First, notice that each term in the equation has a common factor of \(n\). So, factor \(n\) out of the equation: \[ n(8n^2 + 10n + 3) = 0 \]
02
Solve the Factored Equation
Set each factor equal to zero and solve for \(n\). First factor: \[ n = 0 \]Second factor: \[ 8n^2 + 10n + 3 = 0 \]
03
Solve the Quadratic Equation
Now, solve the quadratic equation \( 8n^2 + 10n + 3 = 0 \) using the quadratic formula: \[ n = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]In this case, \(a = 8\), \(b = 10\), and \(c = 3\). Substitute these values in:\[ n = \frac{-10 \pm \sqrt{10^2 - 4(8)(3)}}{2(8)} \]Simplify inside the square root:\[ n = \frac{-10 \pm \sqrt{100 - 96}}{16} \]This simplifies to:\[ n = \frac{-10 \pm 2}{16} \]
04
Simplify the Solutions
Now simplify the expression by splitting it into two separate solutions:\[ n = \frac{-10 + 2}{16} = \frac{-8}{16} = -\frac{1}{2} \]\[ n = \frac{-10 - 2}{16} = \frac{-12}{16} = -\frac{3}{4} \]
05
Combine All Solutions
List all solutions from the previous steps: \( n = 0 \), \( n = -\frac{1}{2} \), and \( n = -\frac{3}{4} \)
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Factoring Polynomials
Factoring polynomials is a fundamental technique for solving higher-degree equations. It involves expressing the polynomial as a product of simpler polynomials. To solve the cubic equation in the exercise, we started by noticing that every term had a common factor of \(n\). Factoring that out, we transformed:
- \(8n^3 + 10n^2 + 3n = 0\) into \(n(8n^2 + 10n + 3) = 0\)
Quadratic Formula
The quadratic formula is an essential tool for solving quadratic equations of the form \(ax^2 + bx + c = 0\).
- Given the quadratic equation \(8n^2 + 10n + 3 = 0\), we apply the quadratic formula: \(n = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\)
- Here, \(a = 8\), \(b = 10\), and \(c = 3\).
Algebraic Solutions
Combining algebraic techniques helps in solving polynomial equations. Starting with the cubic equation:\(8n^3 + 10n^2 + 3n = 0\), we factor out the common term \(n\), leading to:\(n(8n^2 + 10n + 3) = 0\).
- Setting each factor to zero, we solve the simpler equations: \(n = 0\), and \(8n^2 + 10n + 3 = 0\).
- \(n = \frac{-10 + 2}{16} = -\frac{1}{2}\)
- \(n = \frac{-10 - 2}{16} = -\frac{3}{4}\)
- \(n = 0\)
- \(n = -\frac{1}{2}\)
- \(n = -\frac{3}{4}\)