What Is the Probability of Finding a Particle in the Interval [0,d]?

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Nugso
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Homework Statement



Suppose we have a particle in 1-dimension, with wavefunction [tex]Ae^{-\frac{|x|}{2d}}[/tex] . What is the probability to find the particle in the interval [0,d]?
Please provide your answer in terms of A, d, mathematical constants such as π (entered as pi) or e (entered as e). (Assume that A is real)



Homework Equations



[tex]∫ψ²dx = 1[/tex]




The Attempt at a Solution



I think I need to find A by normalizing it. [tex]∫ψ²dx = 1[/tex]

By integrating it, I get [tex]A= 1/\sqrt{2d}[/tex]

Now, I have to integrate it again, but this time with the interval of [0,d]

[tex]∫1/sqrt(2d)*e^{-\frac{|x|}{2d}}*1/sqrt(2d)*e^{-\frac{|x|}{2d}}dx[/tex]

and the answer I'm finding is, [tex]1/2*(1-e^{-1/d})*d[/tex]

But somehow the answer is wrong. How do I correct it?
 
Last edited:
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I would check your solution for A again.
 
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Nugso said:

Homework Statement



Suppose we have a particle in 1-dimension, with wavefunction [tex]Ae^{-\frac{|x|}{2d}}[/tex] . What is the probability to find the particle in the interval [0,d]?
Please provide your answer in terms of A, d, mathematical constants such as π (entered as pi) or e (entered as e). (Assume that A is real)



Homework Equations



[tex]∫ψ²dx = 1[/tex]




The Attempt at a Solution



I think I need to find A by normalizing it. [tex]∫ψ²dx = 1[/tex]

By integrating it, I get [tex]A= 1/\sqrt{2d}[/tex]

Now, I have to integrate it again, but this time with the interval of [0,d]

[tex]∫1/sqrt(2d)*e^{-\frac{|x|}{2d}}*1/sqrt(2d)*e^{-\frac{|x|}{2d}}dx[/tex]

and the answer I'm finding is, [tex]1/2*(1-e^{-1/d})*d[/tex]

But somehow the answer is wrong. How do I correct it?

Check it again. How did you wind up with a -1/d in the exponent?
 
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Sorry for the late reply. I checked it and corrected the mistake.