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Category: Trigonometry

Question-209458

Question Number 209458 by SonGoku last updated on 10/Jul/24 Commented by SonGoku last updated on 10/Jul/24 $$\mathrm{l}\:=\:?\: \\ $$$$\mathrm{BC}\:=\:\:\mathrm{l}\:+\:\mathrm{200m} \\ $$$$\mathrm{B}\hat {\mathrm{A}C}\:=\:\mathrm{120}° \\ $$$$\mathrm{A}\hat {\mathrm{B}C}\:=\:\mathrm{38}°\mathrm{12}'\mathrm{48}''…

Question-208437

Question Number 208437 by efronzo1 last updated on 16/Jun/24 Answered by som(math1967) last updated on 16/Jun/24 $$\:{a}={sin}\mathrm{84}+{cos}\mathrm{66} \\ $$$$\Rightarrow{a}={sin}\mathrm{84}+{sin}\mathrm{24} \\ $$$$\Rightarrow{a}=\mathrm{2}{sin}\mathrm{54}{cos}\mathrm{30} \\ $$$$\:\therefore{a}=\mathrm{2}×\frac{\sqrt{\mathrm{5}}+\mathrm{1}}{\mathrm{4}}×\frac{\sqrt{\mathrm{3}}}{\mathrm{2}}=\frac{\sqrt{\mathrm{3}}\left(\sqrt{\mathrm{5}}+\mathrm{1}\right)}{\mathrm{4}} \\ $$$${b}={sin}\mathrm{48}−{sin}\mathrm{12}…