Chapter 10: Problem 75
Multiply, and then simplify if possible. \((\sqrt{2 x+5}-1)^{2}\)
Short Answer
Expert verified
The simplified expression is \(2x + 6 - 2\sqrt{2x + 5}\).
Step by step solution
01
Expand the Expression
To multiply, first recognize that we have a binomial square. Use the formula \[(a-b)^2 = a^2 - 2ab + b^2\] where \(a = \sqrt{2x + 5}\) and \(b = 1\). Thus, expand the expression to:\[(\sqrt{2x + 5})^2 - 2 \times \sqrt{2x + 5} \times 1 + 1^2\].
02
Simplify Each Term
Now let's calculate and simplify each term:- \((\sqrt{2x + 5})^2\) becomes \(2x + 5\) because squaring a square root cancels the square root.- \(-2 \times \sqrt{2x + 5} \times 1\) simplifies to \(-2\sqrt{2x + 5}\).- \(1^2\) simplifies to \(1\).
03
Combine the Terms
Now, combine all the terms obtained from the previous step:\[2x + 5 - 2\sqrt{2x + 5} + 1\].
04
Simplify the Expression
Combine like terms, which in this case are the constant terms:\[2x + 6 - 2\sqrt{2x + 5}\]. This is the final simplified expression for the given problem.
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.
Simplifying Expressions
Simplifying expressions is a crucial part of algebra that helps in reducing complex expressions into a more manageable form. In our original exercise, simplifying the expression involves both the combination and elimination of terms.
To effectively simplify an expression, follow these steps:
To effectively simplify an expression, follow these steps:
- Identify and group like terms. Like terms have the same variables raised to the same power. In our case, the terms \(5\) and \(1\) are constants and can be combined.
- Apply algebraic operations to reduce the expression further. For example, when we simplify \(5 + 1\), we get \(6\).
- Ensure all terms are expressed in their simplest form. For instance, the term \(2\sqrt{2x + 5}\) is left as is because it cannot be simplified further.
Algebraic Expansion
Algebraic expansion relates to multiplying out expressions, especially when dealing with terms that are raised to a power, such as binomials. In this exercise, we multiplied a binomial using the formula: \[(a-b)^2 = a^2 - 2ab + b^2\]Expanding a binomial squared means turning it into a sum or difference of terms. Here's a recap of how this works in the example:
- The expression \((\sqrt{2x+5} - 1)^2\) is expanded by substituting \(a = \sqrt{2x+5}\) and \(b = 1\).
- Each part of the formula is calculated separately: \(a^2 = (\sqrt{2x+5})^2\), which simplifies to \(2x+5\), \(-2ab = -2 \times \sqrt{2x+5} \times 1\) becomes \(-2\sqrt{2x+5}\), and \(b^2 = 1^2\) which simplifies to \(1\).
- Finally, these simplified terms are combined to form the expanded expression \(2x + 5 - 2\sqrt{2x + 5} + 1\).
Square Roots
Square roots are fundamental in simplifying mathematical expressions, especially when working with quadratic equations and polynomial functions. A square root of a number \(a\), written as \(\sqrt{a}\), is a value that, when multiplied by itself, gives \(a\). In this particular exercise, square roots play a significant role:
- The expression starts with a square root: \(\sqrt{2x+5}\).
- When squaring \(\sqrt{2x + 5}\), it simplifies directly to \(2x + 5\) because the operation of squaring and taking the square root cancels each other out.
- Understanding how square roots interact with other operations, such as multiplication and addition, is key. In this exercise, the expression \(2\sqrt{2x + 5}\) is handled as an intact term, showing that while it cannot be simplified further algebraically, it is crucial to the overall expression.