Chapter 1: Problem 119
Explain why \(-3^{2}\) and \((-3)^{2}\) simplify to different numbers.
Short Answer
Expert verified
\(-3^{2} = -9\) and \((-3)^{2} = 9\); parentheses affect the order of operations.
Step by step solution
01
Understanding the Expression -3²
The expression \(-3^{2}\) involves the exponentiation of the number 3 while maintaining the negative sign outside the exponentiation. It must be interpreted as \(-(3^{2})\), which means we first calculate \(3^{2}\) and then apply the negative sign.
02
Calculating 3²
Calculate \(3^{2}\), which means multiplying 3 by itself. \[ 3^{2} = 3 imes 3 = 9 \]
03
Applying the Negative Sign
After finding \(3^{2} = 9\), apply the negative sign in front to the result. \[ -3^{2} = -(9) = -9 \]
04
Understanding the Expression (-3)²
In the expression \((-3)^{2}\), the negative sign is within the parentheses, meaning the entire term \(-3\) is being squared.
05
Calculating (-3)²
Calculate \((-3)^{2}\), which involves multiplying \(-3\) by itself. \[ (-3)^{2} = -3 imes -3 = 9 \]
06
Comparing Results
From the calculations, \(-3^{2}\) yields -9, while \((-3)^{2}\) yields 9. The parentheses change the operation, squaring the entire term including the negative sign, resulting in different outcomes.
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.
Negative Numbers
Negative numbers are numbers less than zero, represented by a minus sign (-). They are essential in mathematics, especially when dealing with temperatures, debts, or even the opposite direction in physics.
When performing mathematical operations with negative numbers, consider:
When performing mathematical operations with negative numbers, consider:
- A negative sign before a number indicates it is less than zero, such as -5.
- Multiplying two negative numbers results in a positive number, such as \(-2 \times -3 = 6\).
- Adding a negative number means subtracting its absolute value, like \(5 + (-3) = 5 - 3 = 2\).
Parentheses in Expressions
Parentheses play a crucial role in mathematics by determining which operations are performed first. They are used to group numbers and operations, ensuring correct interpretation and calculation.
Consider expressions with and without parentheses:
Consider expressions with and without parentheses:
- Without parentheses: In the expression \(-3^{2}\), the exponent only applies to 3, not the negative sign, because the calculation follows as \-1 \cdot (3^{2})\.
- With parentheses: In the expression \((-3)^{2}\), both the negative number and the number 3 are squared together, as the parentheses group them as one entity, leading to \((-3) \cdot (-3)\).
Order of Operations
The order of operations is a fundamental principle that guides which operations to perform first in a mathematical expression. Known by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction), it ensures consistent and correct results.
- Parentheses: Perform the operations inside parentheses first.
- Exponents: Next, solve any exponents.
- Multiplication and Division: These operations are done from left to right.
- Addition and Subtraction: Finally, perform these operations from left to right.