Kẻ \(MH \bot NL\)
Ta có: \(\sin 30^\circ = \dfrac{{MH}}{{MN}} \Rightarrow MH\)\( = \sin 30^\circ .MN = \sin 30^\circ .2,8\)
\(\sin L = \dfrac{{MH}}{{ML}} = \dfrac{{\sin 30^\circ .2,8}}{{4,2}}\)\( = \dfrac{{0,5.2,8}}{{4,2}} = \dfrac{1}{3} \approx 0,3333.\)
