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Category: Geometry

Question-149031

Question Number 149031 by puissant last updated on 02/Aug/21 Answered by EDWIN88 last updated on 02/Aug/21 $$\Rightarrow\frac{\mathrm{1}+\mathrm{cos}\:\mathrm{2}{x}+\mathrm{1}+\mathrm{cos}\:\mathrm{4}{x}+\mathrm{1}+\mathrm{cos}\:\mathrm{6}{x}}{\mathrm{2}}=\mathrm{1} \\ $$$$\Rightarrow\mathrm{cos}\:\mathrm{6}{x}+\mathrm{cos}\:\mathrm{4}{x}+\mathrm{cos}\:\mathrm{2}{x}=−\mathrm{1} \\ $$$$\Rightarrow\mathrm{2cos}\:\mathrm{4}{x}\:\mathrm{cos}\:\mathrm{2}{x}+\mathrm{cos}\:\mathrm{4}{x}=−\mathrm{1} \\ $$$$\Rightarrow\mathrm{cos}\:\mathrm{4}{x}\left(\mathrm{2cos}\:\mathrm{2}{x}+\mathrm{1}\right)=−\mathrm{1} \\ $$$$\Rightarrow\left(\mathrm{2cos}\:^{\mathrm{2}}…

Question-17948

Question Number 17948 by b.e.h.i.8.3.417@gmail.com last updated on 12/Jul/17 Commented by mrW1 last updated on 12/Jul/17 $$\mathrm{area}\:\mathrm{of}\:\Delta\mathrm{ABC}=\mathrm{S}=\frac{\mathrm{1}}{\mathrm{2}}\mathrm{ah}_{\mathrm{a}} \\ $$$$\Rightarrow\frac{\mathrm{1}}{\mathrm{h}_{\mathrm{a}} }=\frac{\mathrm{1}}{\mathrm{2S}}\:\mathrm{a}=\mathrm{ka} \\ $$$$\mathrm{similarly} \\ $$$$\Rightarrow\frac{\mathrm{1}}{\mathrm{h}_{\mathrm{b}} }=\mathrm{kb}\:…