Chapter 6: Problem 21
Factor each trinomial completely. $$ m^{3}+18 m^{2}+81 m $$
Short Answer
Expert verified
The trinomial is factored as \(m(m + 9)^{2}\).
Step by step solution
01
Identify the Common Factor
First, identify any common factors in the terms of the trinomial. The expression given is \(m^{3} + 18m^{2} + 81m\). Notice that each term has a factor of \(m\). Factoring \(m\) from each term gives us:\[m(m^{2} + 18m + 81)\]
02
Factor the Quadratic Expression
Next, factor the quadratic expression \(m^{2} + 18m + 81\). Look for two numbers that multiply to \(81\) (the constant term) and add up to \(18\) (the coefficient of \(m\)). These numbers are \(9\) and \(9\) since \(9 \times 9 = 81\) and \(9 + 9 = 18\). Thus, the quadratic can be factored as:\[(m + 9)(m + 9)\] which is the same as \((m + 9)^{2}\).
03
Write the Complete Factorization
Combine the factored quadratic back with the common factor from Step 1. The expression now fully factored is:\[m(m + 9)^{2}\].This represents the complete factorization of the original trinomial.
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.
Common Factor
A great start to factoring any trinomial is to find a common factor. In simple terms, a common factor is a number or variable that divides each part of the expression without leaving any leftovers. Think of it as a shared piece among all terms. For the expression \(m^{3} + 18m^{2} + 81m\), notice that each term includes the variable \(m\). This makes \(m\) a common factor.
- Extracting this common factor simplifies the expression, reducing it to \(m(m^{2} + 18m + 81)\).
- This critical first step makes working with the expression easier and sets the stage for further reduction.
Quadratic Expression
Now, let's explore how to factor the quadratic expression \(m^{2} + 18m + 81\). This expression is in a standard quadratic form, which typically looks like \(ax^2 + bx + c\). Here, \(a = 1\), \(b = 18\), and \(c = 81\).
In factoring quadratics like these, the goal is to find two numbers that multiply to the constant term (\(c = 81\)) and add up to the coefficient of the linear term (\(b = 18\)).
In factoring quadratics like these, the goal is to find two numbers that multiply to the constant term (\(c = 81\)) and add up to the coefficient of the linear term (\(b = 18\)).
- The factors we are looking for are both 9 because \(9 \times 9 = 81\) and \(9 + 9 = 18\).
- Thus, the expression can be written as \((m + 9)(m + 9)\), which is the same as \((m + 9)^{2}\).
Complete Factorization
After factoring the quadratic part, combine it back with the common factor. This gives the complete factorization of the original trinomial. For the expression \(m^{3} + 18m^{2} + 81m\), we already factored out \(m\) and reduced it to \((m + 9)^{2}\).
To arrive at the final solution, put the common factor with the factored quadratic:
To arrive at the final solution, put the common factor with the factored quadratic:
- The complete factorization becomes \(m(m + 9)^{2}\).