I think I copied the wrong notes or something because my notes do not follow.(adsbygoogle = window.adsbygoogle || []).push({});

I am trying to find the probability of finding a particle in a box length L in the area [tex]\frac{L}{3}-\frac{\partial}{2}[/tex] to [tex]\frac{L}{3}+\frac{\partial}{2}[/tex]

basically we have the following wave funtion:

[tex]\Phi(x,t)=\sqrt{\frac{2}{3}} \Phi_1 - \sqrt{\frac{1}{3}} \Phi_2[/tex]

so we got the absolute square of the function which gave us probability, then we integrated from [tex]\frac{L}{3}-\frac{\partial}{2}[/tex] to [tex]\frac{L}{3}+\frac{\partial}{2}[/tex]

this gave us the probability, however, we used a short cut, our teacher split P(robability) into 4 parts..

P=I1+I2+I3+I4

then said that I=integrand * del

and came up with a short cut:

[tex]P=\frac{4 \partial}{3L} *\frac{3}{4}+\frac{2}{3} \frac{\partiao}{L} \frac{3}{4}+2 \sqrt{\frac{2}{9}} \frac{2}{L} \sqrt{\frac{3}{4} } \sqrt{\frac{3}{4} }cos\left( \frac{E_2-E_1}{\hbar}t \right)[/tex]

[tex]=\frac{3}{2} \frac{\partial}{L} \left(1+cos\left( \frac{E_2-E_1}{\hbar}t \right) \right)[/tex]

i dont understand this idea of I=integrand * del, could someone direct me to a site that explains this or help me out with this concept?

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# Homework Help: Schrodinger equation

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