tam giác MNK vuông ở M có NK2=MN2+MK2
NK2=25+36=61
NK=\(\sqrt{61}\)
sinN=\(\dfrac{MK}{NK}=\dfrac{6}{\sqrt{61}};cosN=\dfrac{MN}{NK}=\dfrac{5}{\sqrt{61}};tanN=\dfrac{6}{5};cotanN=\dfrac{5}{6}\)
\(sinK=\dfrac{5}{\sqrt{61}};cosK=\dfrac{6}{\sqrt{61}};tanK=\dfrac{5}{6};cotanK=\dfrac{6}{5}\)