Question Number 1113 by 123456 last updated on 15/Jun/15
$$\mathrm{sin}^{−\mathrm{1}} \left[\frac{\sqrt{\mathrm{3}}}{\mathrm{8}}\left(\sqrt{\mathrm{13}}−\mathrm{1}\right)\right]+\mathrm{sin}^{−\mathrm{1}} \frac{\sqrt{\mathrm{3}}}{\mathrm{4}}=? \\ $$