/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 20 Simplify the expression. $$\fr... [FREE SOLUTION] | 91Ó°ÊÓ

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Simplify the expression. $$\frac{\left(e^{x}-e^{-x}\right)^{2}-\left(e^{x}+e^{-x}\right)^{2}}{\left(e^{x}+e^{-x}\right)^{2}}$$

Short Answer

Expert verified
The expression simplifies to \(-\frac{4}{(e^x+e^{-x})^2}\).

Step by step solution

01

Identify the components

We need to simplify the expression \( \frac{(e^x-e^{-x})^2-(e^x+e^{-x})^2}{(e^x+e^{-x})^2} \). Looking at the expression, we notice that both the numerator and the denominator have terms squared, which suggests that we can perhaps use the difference of squares formula: \( a^2 - b^2 = (a-b)(a+b) \). Let \( a = e^x - e^{-x} \) and \( b = e^x + e^{-x} \).
02

Apply the difference of squares formula

Use the identity \( a^2 - b^2 = (a-b)(a+b) \) to rewrite the numerator. Here \( a = e^x - e^{-x} \) and \( b = e^x + e^{-x} \). Thus, \( (e^x - e^{-x})^2 - (e^x + e^{-x})^2 = ((e^x - e^{-x}) - (e^x + e^{-x}))((e^x - e^{-x}) + (e^x + e^{-x})) \).
03

Simplify the expressions inside the product

Calculate the expressions: 1. \((e^x - e^{-x}) - (e^x + e^{-x}) = e^x - e^{-x} - e^x - e^{-x} = -2e^{-x}\)2. \((e^x - e^{-x}) + (e^x + e^{-x}) = e^x - e^{-x} + e^x + e^{-x} = 2e^x\).
04

Simplify the numerator

The numerator becomes the product \((-2e^{-x})(2e^x)\). Simplifying this gives \(-2e^{-x} \times 2e^x = -4\).
05

Divide by the denominator

With the numerator simplified to \(-4\), divide it by the denominator: \( \frac{-4}{(e^x + e^{-x})^2} \). This is the simplest form of the original expression. The expression inside the denominator isn't simplified further since it's already in its simplest form conventionally.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Simplifying Expressions
Simplifying expressions is about rewriting them in a more manageable or concise form. This often involves reducing complex terms into simpler terms. For example, when you encounter expressions with multiple terms or powers, your goal is to reduce or combine these in some way.
  • Look for common factors that can be combined.
  • Use algebraic identities and rules, like factoring or applying differences of squares.
  • Cancel out terms or factors where possible to make the expression smaller or more elegant.
Such strategies not only make expressions easier to understand and compute, they also allow deeper insights into the relationships between variables involved in the equation.
Difference of Squares
The difference of squares is a particular algebraic pattern you can use to simplify expressions. This principle states that any difference of two squared terms can be factored as a product of two binomials:\[a^2 - b^2 = (a - b)(a + b)\]In our exercise, the difference of squares helps break down the complex structure into simpler factors.
This pattern can be especially useful when you need to handle complex polynomial expressions. Recognizing such structures allows you to split the problem into smaller pieces, which are often easier to work with and understand quickly.
Most importantly, it converts multiplications and subtractions into simple multiplicative binomials, streamlining the entire simplification process.
Exponential Functions
Exponential functions, such as those involving the constant \(e\), arise frequently in mathematical problems. The exponential function \(e^x\) is particularly significant because it shows patterns of growth or decay.
Exponentials are often handled on their own or combined using algebraic rules:
  • When expressions have exponents, look for common bases to simplify terms.
  • If a term is inversely related, like \(e^{-x}\), it represents the reciprocal \(\frac{1}{e^x}\).
  • Simplifying exponents often involves recognizing and manipulating these reciprocal relationships.
Understanding exponentials and their properties is central to solving many algebraic problems effectively. The manipulation of these terms requires knowledge of basic exponent rules and an ability to rewrite terms in a format that allows simplification.
Algebraic Manipulation
Algebraic manipulation involves systematically changing the form of an expression to reveal its simplest or most useful form. This involves numerous techniques:
  • Combining like terms to reduce the number of separate components in an expression.
  • Implementing identities, such as \(a + b\) and \(a - b\), in context to solve for specific variables or to simplify expressions.
  • Dividing or multiplying through common terms simplifies fractions and reveals a more predictable structure.
Consider our exercise, where manipulating the expressions through steps such as expanding, factoring, and simplifying plays a critical role in achieving the final, simplified expression. Bold algebraic manipulation also provides insights into the behaviors and relationships of various mathematical components within expressions.

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