Wavefunction and shroedinger equation

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Homework Statement



Typed homework problem 3 asking to check that the n=1, l=0, m=0 wavefunction φ(r) = C e^(-2r/a_B) satisfies the Schrödinger equation and find the constant C.


Homework Equations



Time-independent Schrödinger equation for a hydrogen-like atom in spherical coordinates: [-(ħ²/2m)∇² - kZe²/r] φ(r,θ,φ) = Eφ(r,θ,φ).


The Attempt at a Solution



First, I got the wavefunction to look like the one in the question. I think the wavefunction should be n=1 not n=0. So Y(theta,psi) = A constant, that is where the C comes from. But how can I plug this into the shrodinger equation? How can I answer this question?
 
In the Schrödinger equation, there is a differentiation operator ([itex]-\frac{\hbar^2}{2m} \nabla^2[/itex] )and a multiplication-by-a-function([itex]-\frac{kZe^2}{r}[/itex]) operator. You just should apply those operators to [itex]\phi_{0,0,0}(\vec r)[/itex] and add the results and check whether you get a constant times [itex]\phi_{0,0,0}(\vec r)[/itex].
For [itex]-\frac{\hbar^2}{2m} \nabla^2[/itex], you should first take the gradient of [itex]\phi_{0,0,0}(\vec r)[/itex] which gives you a vector field which you should get the divergence of. Then multiply by [itex]-\frac{\hbar^2}{2m}[/itex].
 
Alternatively to the two step approach in first taking the gradient and then the divergence of the gradient, you could apply the Laplace operator in spherical coordinates directly:
$$
\nabla^2 = \frac{1}{r^2}\frac{\partial}{\partial r} r^2 \frac{\partial}{\partial r} = \frac{\partial^2}{\partial r^2} + \frac{2}{r} \frac{\partial}{\partial r} ,
$$
where I have removed the angular part since your wave function does not depend on the angles.