How to determine a Limits of Integration of Wave Packet

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To determine the normalization constant A for the given wave packet, the integration limits must be carefully defined based on the piecewise function provided. The first integral should cover the region where the wave function is non-zero, specifically from -a - ε to a + ε. The integration will involve summing the contributions from each segment of the wave packet, including the constant A for |x| ≤ a, and the linear segments for the intervals a < x ≤ a + ε and -a - ε ≤ x < a. The key is to ensure that the total integral equals one for normalization. Properly identifying these limits is crucial for calculating A and subsequently the mean values and variances of the position and momentum operators.
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Homework Statement


Consider a force-free particle of mass m described, at an instant of time t = 0, by
the following wave packet:
<br /> \begin{array}{l}<br /> 0 \ \mathrm{for} \ |x| &gt; a + \epsilon \\<br /> A \ \mathrm{for} \ |x| ≤ a \\<br /> -\frac{A}{\epsilon} (x − a − \epsilon) \ \mathrm{for} \ a &lt; x ≤ a + \epsilon \\<br /> \frac{A}{\epsilon}(x + a + \epsilon) \ \mathrm{for} \ − a − \epsilon ≤ x &lt; a \\<br /> \end{array}<br />
where a, ε, and a normalization constant A are all positive numbers. Calculate mean
values and variances of the position and momentum operators x , x^{2} , \sigma_{x} \ and \ p_{x} .

Homework Equations


<br /> 1=\int_{-\infty}^{\infty} |\psi(x,t)|^{2}<br />

The Attempt at a Solution


I want to determine normalization constant A. I don't know what kind of integration limits i should use for the case:
A \ \mathrm{for} \ |x| ≤ a.
Do you have any ideas ? Thanks in advance !
 
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You have a lot of intervals and need to use the fact that the integral will be a sum of integrals for each interval. So write all the integrals, compute them all the find A. Then compute all other items.
 
Ok , so far i have:
\int_{??}^{??} A^{2} dx (?) -\frac{A^{2}}{\epsilon^{2}}\int_{a}^{a+\epsilon} (x-a-\epsilon)^{2} dx +\frac{A^{2}}{\epsilon^{2}}\int_{-a-\epsilon}^{a} (x+a+\epsilon)^{2} dx =1. My question is what are the integration limits for the first integral ?
 
Where did you pick the first one from ? Is there an interval where the wavefunction is 1 ?
 
So, should i include first integral ? That was my problem/question ?
 

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