The Attempt at a SolutionWhat is the Normalized Function for Y(k) = A(a-|k|)?

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The discussion focuses on normalizing the function Y(k) = A(a - |k|) for |k| ≤ a and Y(k) = 0 for |k| > a. Participants express confusion about the shape of the function and how to solve the integral of Y^2 for normalization. The normalization requires calculating the integral over the entire range of k, not just from a to infinity. Clarifications are sought regarding the correct representation of the function and the area under the curve for proper normalization. The conversation emphasizes the importance of understanding the function's behavior and the integral's limits to achieve normalization.
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Homework Statement


I have to normalize the function below:
Y(k)= A (a-|k|) where |k|<=a ; And Y(k)=0 where |k|>a

Homework Equations

The Attempt at a Solution



I just get to infinity.
 
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I just get to infinity.
... how?
Y(k)= A (a-|k|) where |k|<=a ; And Y(k)=0 where |k|>a
... sketch Y vs k for the function.
What shape is it? What is the equation for the area of that shape?
 
I know how does it shape but I still don't understand how does the integral of Y^2 should be solved.
 
I know how does it shape...
... so what is the shape? If you don't answer questions it is difficult to help you.

... but I still don't understand how does the integral of Y^2 should be solved.
Show me what you are trying.
Unless I see how you are thinking I don't know how to help you.
 
Last edited:
First one is what I got in normalizing. I can't solve the last two integrals while the fist one is infinity.
And below is what I guess the shape of the function Y(k) should be.
image.jpg
 
OK, you are starting out with: ##Y(k)=A(a-|k|) : |k|<a, 0 \text{ otherwise}##

To normalize ##Y##, you need to find ##A: \int_{-\infty}^\infty Y^\star Y\;dk = 1## Since Y is real, ##Y^\star Y = Y^2##

In your attachment I only see you taking the range from a to +infinity.
But the wavefunction is defined over all values of k.

Note: you are mistaken about what shape the wavefunction is;
... what is the value of Y when k > a? What did you put on your sketch?
 
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