Question

[Quoc Tran Anh Le]

a) Tính \(\cos {80^o}43'51'';\tan {147^o}12'25'';\cot {99^o}9'19''.\)

b) Tìm \(\alpha \;({0^o} \le \alpha  \le {180^o}),\) biết \(\cos \alpha  =  - 0,723.\)

Answer 1

[Hà Quang Minh]

a)

\(\begin{array}{l}\cos {80^o}43'51'' = 0,161;\\\tan {147^o}12'25'' =  - 0,644;\\\cot {99^o}9'19'' =  - 0,161\end{array}\)

b) \(\alpha  = {136^o}18'9,81''.\)