To find I suggest making the substitution .
Note that is a famous definite integral. See Gaussian Integral -- from Wolfram MathWorld
I have already shown T(x,t) = (A/sqrt(t))*exp((-x^2)/(4kt))
is a solution of the wave equation
I now need to show int (T(x,t)) dx between infinity and neg infinity is a constant function of T
obvioulsy I cant integrate the function.. I know integrating the wave equation would give me [(t^2)/2] is this enough to say?
To find I suggest making the substitution .
Note that is a famous definite integral. See Gaussian Integral -- from Wolfram MathWorld
Brilliant, thankyou
I have another wave equation problem
http://people.maths.ox.ac.uk/~earl/sheet5b.pdf
question 3
I have verified it is a solution
now applying ICs I get
sum {sin(n.pi.x/l)[A_n] = alpha sin(pi.x/l)}
which I cant see how I would get A_n
many thanks