What is the Integral of ln(2x+1)?

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In summary, the conversation is about finding the integral of ln(2x+1)dx using integration by parts. The attempt involves using u-substitution and polynomial long division to simplify the integral.
  • #1
Sczisnad
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Homework Statement


integral ln(2x+1)dx


Homework Equations


N/A


The Attempt at a Solution


I tried integration by parts,

Let u = ln(2x+1), dv = dx, du = 2/(2x+1)dx, v = x

ln(2x+1)dx = ln(2x+1)*x-(integral)x*(2/(2x+1))dx
 
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  • #2
Try u-substitution with [itex]u=2x+1[/itex].
 
  • #3
Sczisnad said:

Homework Statement


integral ln(2x+1)dx


Homework Equations


N/A


The Attempt at a Solution


I tried integration by parts,

Let u = ln(2x+1), dv = dx, du = 2/(2x+1)dx, v = x

ln(2x+1)dx = ln(2x+1)*x-(integral)x*(2/(2x+1))dx
So far, so good. The last integral can be turned into a simpler one by dividing 2x by 2x + 1, using polynomial long division. If you don't know that technique, it works out to 1 + -1/(2x + 1) in this problem.
 
  • #4
Try u subsitution (the obvious one...)
 

1. What does it mean to "evaluate the integral"?

Evaluating the integral means finding the exact numerical value of a definite integral, which represents the area under a curve in a given interval. It is a way to measure the accumulation of a quantity over a certain range.

2. How do you evaluate an integral?

To evaluate an integral, you can use various techniques such as substitution, integration by parts, or the fundamental theorem of calculus. You can also use numerical methods like the trapezoidal rule or Simpson's rule.

3. What is the difference between definite and indefinite integrals?

A definite integral has specific limits of integration, which means it represents a specific area under a curve. An indefinite integral has no limits and represents a general antiderivative of a function.

4. Can all integrals be evaluated analytically?

No, not all integrals can be evaluated analytically. Some integrals have no closed form solution and can only be approximated using numerical methods.

5. What is the significance of evaluating integrals in science?

Evaluating integrals is essential in many fields of science, such as physics, engineering, and economics. It allows us to calculate important quantities such as displacement, velocity, work, and profit, which are crucial for understanding real-world phenomena and making predictions.

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