/*! 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 35 Solve the equation. \(4 x^{3} ... [FREE SOLUTION] | 91Ó°ÊÓ

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Solve the equation. \(4 x^{3} e^{-3 x}-3 x^{4} e^{-3 x}=0\)

Short Answer

Expert verified
The solutions are \(x = 0\) and \(x = \frac{4}{3}\).

Step by step solution

01

Factor Out Common Terms

Notice that both terms in the equation share the common factors of \(x^3\) and \(e^{-3x}\). Factor these out to get:\[4x^3 e^{-3x} - 3x^4 e^{-3x} = x^3 e^{-3x}(4 - 3x) = 0\]
02

Set Each Factor to Zero

Once the equation is factored, apply the zero product property, which states that if a product equals zero, at least one of the factors must be zero:1. \(x^3 = 0\)2. \(e^{-3x} = 0\)3. \((4 - 3x) = 0\)
03

Solve \(x^3 = 0\)

Solve \(x^3 = 0\) by taking the cube root of both sides, resulting in:\[x = 0\]
04

Solve \(e^{-3x} = 0\)

The exponential function \(e^{-3x}\) is never zero for any real numbers \(x\). Therefore, there is no solution from the factor \(e^{-3x} = 0\).
05

Solve \(4 - 3x = 0\)

Solve \(4 - 3x = 0\) by isolating \(x\). Subtract 4 from both sides and divide by -3:\[3x = 4 \x = \frac{4}{3}\]
06

Write the Final Solutions

The solutions to the equation come from solving each of the factors that we set to zero. Therefore, the solutions are:\[x = 0 \quad \text{and} \quad x = \frac{4}{3}\]

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Key Concepts

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

Factoring
Factoring is a key skill in algebra that involves breaking down complex expressions into simpler components. Think of it as unraveling a complicated sewing pattern into its basic pieces. In the exercise given, we started with an equation involving the terms \(4x^3 e^{-3x}\) and \(-3x^4 e^{-3x}\). Both terms have \(x^3\) and \(e^{-3x}\) in common. By factoring, we pulled out these common elements, simplifying the equation into \(x^3 e^{-3x}(4 - 3x) = 0\). The process of finding these common elements requires identifying the greatest common factor, which here is \(x^3 e^{-3x}\). This step helps to reduce complexity and makes the problem easier to solve. Factoring is useful because it sets us up for the application of other algebraic principles, like the zero product property.
Zero Product Property
The zero product property is crucial when solving algebraic equations that have been factored. It tells us that if the product of two or more terms is zero, then at least one of the terms must be zero. This principle is particularly useful when working with polynomials.In the context of our exercise, after factoring the equation, we ended up with \(x^3 e^{-3x}(4 - 3x) = 0\). According to the zero product property, we set each factor to zero:
  • \(x^3 = 0\)
  • \(e^{-3x} = 0\)
  • \(4 - 3x = 0\)
Setting each factor to zero and solving those mini-equations is how we find potential solutions for the original equation. It's like saying if any part of the machine isn't working (i.e., it equals zero), the whole machine doesn't work.
Exponential Functions
Exponential functions, such as \(e^{-3x}\), play a significant role in mathematics, especially in calculations involving growth and decay. They are unique because they have a constant base (in this case, Euler's number \(e\)) raised to a variable exponent. One interesting property of exponential functions is that they never equal zero. No matter what value \(x\) takes, \(e^{-3x}\) produces a positive number. This is why in our exercise, the equation \(e^{-3x} = 0\) has no solutions. Understanding this characteristic is critical because it allows us to eliminate one potential source of solutions early.Exponential functions are common in real-life scenarios like calculating compound interest, population growth, or radioactive decay, where change accumulates at a consistent relative rate.
Solutions to Equations
Finding solutions to algebraic equations involves determining the values of variables that make the equation true. Solving an equation is like finding the key that unlocks a door; each solution is a possible value that satisfies the equation.In this exercise, we solved the factored form \(x^3 e^{-3x}(4 - 3x) = 0\) by utilizing the zero product property. We identified two solutions:
  • \(x = 0\)
  • \(x = \frac{4}{3}\)
These values make the original equation true when substituted back into it. Solving equations may sometimes involve verifying solutions, especially when dealing with complex expressions. We analyze each component of the equation methodically to ensure every solution aligns with the original equation. This methodical approach helps cultivate a deeper understanding of how equations function and interrelate with broader mathematical concepts.

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