How to reduce Einstein's equation for perfect fluids

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Using the metric $$ds^2=-V^2 dt^2 +g_{ab} dx^a dx^b$$, where $$g_{ij}$$ is the Riemannian metric of the constant t-surfaces, and V is the gravitational potential, show that Einstein's equation $$G_{ij}=8\pi T_{ij}$$ for perfect fluids reduces to the system
$$D^a D_a V= 4 \pi V( \rho +3p)\\
R_{ab}=V^{-1}D_a D_b V+4 \pi ( \rho -p) g_{ab}$$
Where $$D_a$$ and $$R_{ab}$$ are the three dimensional covariant derivative and Ricci curvature tensor associated with $$g_{ab}$$.
 
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Is this a homework question? Have you tried it yourself?
 
No its not a homework question, I read it in an article by J. of Math Phys 29 (2) feb 1988. Static uniform density stars must be spherical in GR
 
I'm sorry, could you write the whole line element? I don't know the components of g_{ij} expliclity.
 
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