Chapter 28: Problem 7
Integrate each of the given functions. $$\int_{-2}^{2} 6 e^{s / 2} d s$$
Short Answer
Expert verified
The definite integral evaluates to \( 12(e - \frac{1}{e}) \).
Step by step solution
01
Identify the Function to Integrate
The function given for integration is \( 6 e^{s/2} \). We are instructed to perform definite integration from \(-2\) to \(2\).
02
Determine the Antiderivative
To integrate \( 6 e^{s/2} \) with respect to \( s \), we need to find its antiderivative. Notice that it is a basic exponential function. The integral of \( e^{ks} \) is \( \frac{1}{k} e^{ks} \). In this case, \(k = \frac{1}{2}\). So, the antiderivative of \( e^{s/2} \) is \( 2e^{s/2} \). Therefore, the antiderivative of the whole expression \( 6 e^{s/2} \) is \( 12e^{s/2} \).
03
Evaluate the Indefinite Integral
The indefinite integral of the function is \( 12e^{s/2} + C \). However, since we are evaluating a definite integral, we'll use the antiderivative without the constant \( C \) for the evaluation.
04
Apply the Fundamental Theorem of Calculus
For the definite integral, evaluate the antiderivative from \(-2\) to \(2\). Thus, compute \( F(2) - F(-2) \) where \( F(s) = 12e^{s/2} \).
05
Calculate the Values of the Antiderivative
First, calculate \( F(2) = 12e^{2/2} = 12e^1 = 12e \). Then, calculate \( F(-2) = 12e^{-2/2} = 12e^{-1} = 12 / e \).
06
Subtract to Find the Definite Integral
Now subtract the two results: \( F(2) - F(-2) = 12e - 12/e \). This simplifies to \[ 12\left(e - \frac{1}{e}\right) \].
07
Final Calculation and Simplification
This is the final result of the definite integral. Therefore, the value of the integral is \( 12(e - \frac{1}{e}) \). The expression could be left in this form or further simplified if needed.
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.
Antiderivative
An antiderivative of a function is another function whose derivative is the original function you started with. Essentially, it's like "reverse-differentiating." For any function you wish to integrate, finding the antiderivative is the initial step.
In our exercise, we handle the function \(6e^{s/2}\). To find its antiderivative, recall the rule for integrating exponential functions, \(e^{ks}\), which states that the integral is \(\frac{1}{k}e^{ks}\). Here, the constant \(k\) is \(\frac{1}{2}\), making the antiderivative of \(e^{s/2}\) equal to \(2e^{s/2}\). Therefore, for \(6e^{s/2}\), multiplying by 6 gives \(12e^{s/2}\).
In our exercise, we handle the function \(6e^{s/2}\). To find its antiderivative, recall the rule for integrating exponential functions, \(e^{ks}\), which states that the integral is \(\frac{1}{k}e^{ks}\). Here, the constant \(k\) is \(\frac{1}{2}\), making the antiderivative of \(e^{s/2}\) equal to \(2e^{s/2}\). Therefore, for \(6e^{s/2}\), multiplying by 6 gives \(12e^{s/2}\).
- Antiderivative of \(e^{ks}\) is \(\frac{1}{k}e^{ks}\).
- Adjust by constants like 6 to find the full antiderivative, which results in multiplying the antiderivative by 6.
Fundamental Theorem of Calculus
The Fundamental Theorem of Calculus bridges the concepts of differentiation and integration, providing a way to evaluate definite integrals via antiderivatives. This theorem simplifies the process significantly.
According to this theorem, if you have a continuous function \(f\) and its antiderivative \(F\), the definite integral of \(f\) from \(a\) to \(b\) can be evaluated by \(F(b) - F(a)\). This eliminates the constant term \(C\) you normally add when finding an indefinite integral because it cancels out when subtracting the antiderivative values.
According to this theorem, if you have a continuous function \(f\) and its antiderivative \(F\), the definite integral of \(f\) from \(a\) to \(b\) can be evaluated by \(F(b) - F(a)\). This eliminates the constant term \(C\) you normally add when finding an indefinite integral because it cancels out when subtracting the antiderivative values.
- First compute \(F(b) = 12e^{b/2}\).
- Then compute \(F(a) = 12e^{a/2}\).
- Finally, subtract: \(F(b) - F(a)\) to get your definite integral.
Exponential Functions
Exponential functions have a constant base raised to a variable exponent, taking the form \(ae^{bx}\). Here, \(a\) controls the function's amplification, whereas \(b\) affects how quickly the function changes.
Typically, integration involving exponential functions follows a straightforward pattern given by their easy-to-identify form. In our example, \(6e^{s/2}\), the base \(e\) stays consistent while the variable \(s\) in the exponent alters solutions based on what's multiplied (\(1/2\) in this case).
Typically, integration involving exponential functions follows a straightforward pattern given by their easy-to-identify form. In our example, \(6e^{s/2}\), the base \(e\) stays consistent while the variable \(s\) in the exponent alters solutions based on what's multiplied (\(1/2\) in this case).
- Recognize forms: \(ae^{bx}\) leads to solutions of \(\frac{a}{b}e^{bx}\).
- Adjust for multipliers, as we saw with the leading 6 becoming 12 due to \(\frac{1}{1/2}\) turning into 2.