Uncertainty in position for eigenstates (Liboff 3.10)

WyoChuck
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Homework Statement



From Liboff edition 4:

For the state

ψ(x,t)=A exp(x-x0)2 / {4a2} * exp(ip0x)/hbar * exp (-iω0t)

show that (Δx)2 = a2

then argue the consistency of this conclusion with the change in shape that |ψ2| suffers with a change in the parameter a

Homework Equations



Equations given in problem as well as

(Δx)2 = <(x-<x>2)>


The Attempt at a Solution



So far I've tried substituting in Δx and using algebra to eliminate variables as well as solving for just a but unfortunatly have been unable to make and leeway into proving the solution. In general I'm just lost as to where to start and any usefull advice will come in quite handy.
 
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WyoChuck said:
[STRIKE][/STRIKE]

Homework Statement



From Liboff edition 4:

For the state

ψ(x,t)=A exp(x-x0)2 / {4a2} * exp(ip0x)/hbar * exp (-iω0t)

show that (Δx)2 = a2

then argue the consistency of this conclusion with the change in shape that |ψ2| suffers with a change in the parameter a

Homework Equations



Equations given in problem as well as

(Δx)2 = <(x-<x>2)>


The Attempt at a Solution



So far I've tried substituting in Δx and using algebra to eliminate variables as well as solving for just a but unfortunatly have been unable to make and leeway into proving the solution. In general I'm just lost as to where to start and any usefull advice will come in quite handy.
I have no idea what "substituting in Δx and using algebra to eliminate variables as well" means. Show your actual work.
 
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