- 4

- 0

ψ (x,t)= N sin (kx) e

^{-iEt/hbar}

but when I compared to what I read from a modern physics book written by Beisser. the wavefunction is:

d

^{2}ψ/dx

^{2}+ 2m/hbar E ψ

=0

and the solution is:

ψ=A sin ((√2mE)/hbar)x + B cos ((√2mE)/hbar)

and we only use:

ψ =N sin (kx) only,

it is different. and I got trouble when I tried to find momentum probability. because it is different. which one is true?

my question is:

1.where "e

^{-iEt/hbar}" comes from?

2. how to get the solution "

ψ=A sin ((√2mE)/hbar)x + B cos ((√2mE)/hbar)" from

d

^{2}ψ/dx

^{2}+ 2m/hbar E ψ

= 0

thank you very much for help.. :)