/*! 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 7 Evaluate the following integrals... [FREE SOLUTION] | 91Ó°ÊÓ

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Evaluate the following integrals or state that they diverge. $$\int_{-\infty}^{0} e^{x} d x$$

Short Answer

Expert verified
If it converges, what is its value? Answer: The integral converges, and its value is 1.

Step by step solution

01

Identify the integrand and the limits of integration

The function we need to integrate is \(e^x\), and the given limits of integration are from \(-\infty\) (negative infinity) to 0.
02

Find the antiderivative of the integrand

The antiderivative of \(e^x\) is itself, that is, the indefinite integral of \(e^x\) with respect to x is \(e^x + C\), where C is the constant of integration. We don't need to worry about the constant of integration for now, as it will be eliminated when we evaluate the definite integral.
03

Evaluate the definite integral

Now, we need to evaluate the integral of \(e^x\) with the given limits of integration. This can be done by finding the difference between the antiderivative at the upper and lower limits of integration as follows: $$\int_{-\infty}^{0} e^x dx = \left[e^x\right]_{-\infty}^{0}$$
04

Calculate the integral at the limits of integration

To find the integral at the limits of integration, we simply plug in the limits into the antiderivative: At the upper limit, \(x=0\): $$e^0 = 1$$ At the lower limit, \(x=-\infty\): We know that as \(x\) goes to \(-\infty\), \(e^x\) goes to 0. Therefore, the lower limit evaluates to 0: $$\lim_{x\to-\infty} e^x = 0$$
05

Subtract the value of the antiderivative at the lower limit from the value at the upper limit

Finally, we find the difference between the value of the antiderivative at the upper limit and the lower limit: $$\int_{-\infty}^{0} e^x dx = 1 - 0 = 1$$ The integral converges to 1.

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Most popular questions from this chapter

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