Three phase power supply - what is line to line voltage

Well this seems like a basic principle, yet I can't seem to get it. (We're expect to "know" this already).

In a three phase situation I'm given a source voltage of 230V. - So the waveform of each of the phases would be: $ v_s = \sqrt2 \cdot 230 \cdot \sin(\omega t + \theta_i)$

Where $\theta_i$ is $0, \tfrac{2}{3} \pi, \tfrac{4}{3} \pi$ for each phase.

So now I could calculate the line to line voltage by the formula:

$$v_{ll} = 2 \cdot \left ( \sqrt2 \cdot 230 \cdot \sin(\tfrac{2}{3} \pi) \right)$$

Is this correct?