Calculate Riemann tensor according to veilbein

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Homework Statement


How to use veilbein to calculate Riemann tensor, Ricci tensor and Ricci scalar?
(please give me the details)
[itex]de^a+\omega_{~b}^a\wedge e^b=0[/itex],
[itex]R_{~b}^a=d\omega_{~b}^a+\omega_{~c}^a\wedge\omega_{~b}^c[/itex].
The metric is
[itex]ds^2=-e^{2\alpha(r)}dt^2+e^{2\beta(r)}dr^2+r^2d\theta^2+r^2\sin^2\theta d\phi^2[/itex].
(Sean Carroll, page 195).


Homework Equations


the metric is:
[itex]ds^2=-e^{2\alpha(r)}dt^2+e^{2\beta(r)}dr^2+r^2d\theta^2+r^2\sin^2\theta d\phi^2[/itex].
the veilbeins:
[itex]e^0=e^\alpha dt,~~e^1=e^\beta dr,~~e^2=rd\theta,~~e^3=r\sin\theta d\phi[/itex].

[itex]de^a+\omega_{~b}^a\wedge e^b=0[/itex].

1. [itex]de^0+\omega_{~1}^0\wedge e^1=0[/itex]
[itex]\alpha'e^\alpha dr\wedge dt+\omega_{~1}^0\wedge e^\beta dr=0[/itex]
[itex]~~~\omega_{~1}^0=\alpha'e^\alpha e^{-\beta}dt[/itex].

2. [itex]de^2+\omega_{~1}^2\wedge e^1=0[/itex]
[itex]dr\wedge d\theta+\omega_{~1}^2\wedge e^\beta dr=0[/itex]
[itex]~~~\omega_{~2}^1=-e^{-\beta}d\theta[/itex].

3. [itex]de^3+\omega_{~1}^3\wedge e^1=0[/itex]
[itex]\sin\theta dr\wedge d\phi+\omega_{~1}^3\wedge e^\beta dr=0[/itex]
[itex]~~~\omega_{~3}^1=-e^{-\beta}\sin\theta d\phi[/itex].

4. [itex]de^3+\omega_{~2}^3\wedge e^2=0[/itex]
[itex]r\cos\theta d\theta\wedge d\phi+\omega_{~2}^3\wedge rd\theta=0[/itex]
[itex]~~~\omega_{~3}^2=-\cos\theta d\phi[/itex].

I only calculate 4 spin connections, but how to calculate [itex]\omega_{~2}^0,~\omega_{~3}^0[/itex]?

The Attempt at a Solution

 
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Why did you skip summations over index b in the first formula? Why do you have only one term there?