Can You Help Me Solve This Tricky Integral?

  • Thread starter philipc
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In summary, the conversation is about solving an integral involving exponential and algebraic functions. The participants suggest using substitution to simplify the problem and find the correct answer.
  • #1
philipc
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just wonder if someone could help me solve this integral,
thanks

(e^-2x) / (1+e^-x)
 
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  • #2
Can you integrate (t2) / (1 + t)? I'm guessing that's how you should do it, since I don't really know... :tongue:
 
  • #3
philipc said:
just wonder if someone could help me solve this integral,
thanks

(e^-2x) / (1+e^-x)

Do some algebraic manipulation of the original problem. If you do, the problem wil reduce to a form that allows U substitution.
 
  • #4
I think Chen was on the right track, ie, use substitution t = e^-x
but don't forget about dx -- should come to a much simpler integration
 
  • #5
k..substitute u = (1 + e^-x)...then find du...work from there...and you should get the correct answer...
...hint...remember that u-1 = e^-x...
 
1.

What is the definition of the integral (e^-2x) / (1+e^-x)?

The integral (e^-2x) / (1+e^-x) represents the area under the curve of the function (e^-2x) / (1+e^-x) from x=0 to x=∞.

2.

What is the general formula for solving integrals involving exponential functions?

The general formula for solving integrals involving exponential functions is: ∫e^ax dx = (1/a)e^ax + C, where a is a constant and C is the constant of integration.

3.

How do you solve the integral (e^-2x) / (1+e^-x)?

To solve the integral (e^-2x) / (1+e^-x), we can use the substitution method. Let u = 1+e^-x, then du=-e^-x dx. Substituting into the integral, we get ∫(e^-2x) / (1+e^-x) dx = ∫(1/u) (-du) = -ln(u) + C = -ln(1+e^-x) + C.

4.

What is the significance of the constant of integration in the integral (e^-2x) / (1+e^-x)?

The constant of integration represents the unknown value that is added to the result of the integral. This is because when we take the derivative of a constant, it equals 0. In the case of indefinite integrals, we must always include the constant of integration in the solution.

5.

Is the integral (e^-2x) / (1+e^-x) convergent or divergent?

Since the function (e^-2x) / (1+e^-x) approaches 0 as x approaches ∞, the integral is convergent. This means that the area under the curve is finite and can be calculated using the given formula.

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