câu 1:
sin 105* = $\frac{√6 +√2 }{4}$
cos 105* = $\frac{-√6 +√2 }{4}$
tan 105* = -2-√3
câu 2:
sin 165* = $\frac{√6 -√2 }{4}$
cos 165* = -$\frac{√6+√2}{4}$
tan 165* = -2+√3
cot 165* = -2-√3
câu 4:
a) cos$\frac{37\pi}{12}$ = -$\frac{√6 +√2 }{4}$
b) sin$\frac{33\pi}{4}$ = $\frac{√2}{2}$
c) tan$\frac{73\pi}{3}$ = √3
d) cot$\frac{109\pi}{6}$ = √3