Which substitution transforms x2y′′+xy′+(x2−n2)y=0x^2 y'' + xy' + (x^2 - n^2)y = 0x2y′′+xy′+(x2−n2)y=0 into the Bessel equation?
It is already the Bessel equation.
x=lntx = \ln tx=lnt
y=uny = u^ny=un
y=xnuy = x^n uy=xnu