Question Number 10363 by Joel575 last updated on 05/Feb/17 $$\Delta{ABC}\:\mathrm{with}\:{AB}\:=\:\mathrm{5},\:{BC}\:=\:\mathrm{7},\:{CA}\:=\:\mathrm{8} \\ $$$$\mathrm{Find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of} \\ $$$$\left(\mathrm{sin}\:{A}\:+\:\mathrm{sin}\:{B}\:+\:\mathrm{sin}\:{C}\right)\:.\:\left(\mathrm{cot}\:\frac{{A}}{\mathrm{2}}\:+\:\mathrm{cot}\:\frac{{B}}{\mathrm{2}}\:+\:\mathrm{cot}\:\frac{{C}}{\mathrm{2}}\right) \\ $$ Answered by mrW1 last updated on 06/Feb/17 $${a}={BC}=\mathrm{7} \\…
Question Number 75901 by Master last updated on 20/Dec/19 Answered by MJS last updated on 20/Dec/19 $$\frac{\mathrm{1}}{\mathrm{cos}^{\mathrm{2}} \:{x}}=\mathrm{4tan}\:\mathrm{2}{x} \\ $$$$\frac{\mathrm{1}}{\mathrm{1}+\mathrm{cos}\:\mathrm{2}{x}}=\mathrm{2tan}\:\mathrm{2}{x} \\ $$$${x}=\mathrm{arctan}\:{t} \\ $$$$\frac{{t}^{\mathrm{2}} +\mathrm{1}}{\mathrm{2}}=\frac{\mathrm{4}{t}}{\mathrm{1}−{t}^{\mathrm{2}}…
Question Number 141412 by bramlexs22 last updated on 18/May/21 $$\:{Find}\:{the}\:{range}\:{of}\:{real}\:{number} \\ $$$${of}\:{q}\:{such}\:{that}\:{the}\:{function}\: \\ $$$$\:{f}\left({x}\right)\:=\:\mathrm{cos}\:{x}\left({q}\:\mathrm{sin}\:^{\mathrm{2}} {x}−\mathrm{5}\right)\:{have} \\ $$$${minimum}\:{value}\:{is}\:−\mathrm{5}\:. \\ $$ Commented by MJS_new last updated on…
Question Number 75868 by Crabby89p13 last updated on 19/Dec/19 $${PROVE}\:\:{THAT} \\ $$$$ \\ $$$$\mathrm{sin3}°\:\mathrm{sin39}°\:\mathrm{sin75}°\:=\:\mathrm{sin}\:\mathrm{9}°\:\mathrm{sin}\:\mathrm{24}°\:\mathrm{sin}\:\mathrm{30}° \\ $$ Terms of Service Privacy Policy Contact: info@tinkutara.com
Question Number 10265 by Tawakalitu ayo mi last updated on 31/Jan/17 $$\mathrm{From}\:\mathrm{the}\:\mathrm{top}\:\mathrm{of}\:\mathrm{a}\:\mathrm{100}\:\mathrm{m}\:\mathrm{high}\:\mathrm{building},\:\mathrm{a}\:\mathrm{man} \\ $$$$\mathrm{observes}\:\mathrm{the}\:\mathrm{top}\:\mathrm{of}\:\mathrm{a}\:\mathrm{tree}\:\mathrm{at}\:\mathrm{an}\:\mathrm{angle}\:\mathrm{of} \\ $$$$\mathrm{depression}\:\mathrm{30}°.\:\mathrm{If}\:\mathrm{the}\:\mathrm{tree}\:\mathrm{is}\:\mathrm{50}\:\mathrm{m}\:\mathrm{tall},\:\mathrm{the} \\ $$$$\mathrm{angle}\:\mathrm{of}\:\mathrm{depression}\:\mathrm{of}\:\mathrm{the}\:\mathrm{foot}\:\mathrm{of}\:\mathrm{the}\:\mathrm{tree}\:\mathrm{is} \\ $$$$\mathrm{viewed}\:\mathrm{by}\:\mathrm{the}\:\mathrm{man}\:\mathrm{is}\:? \\ $$ Answered by sandy_suhendra…
Question Number 10227 by Tawakalitu ayo mi last updated on 30/Jan/17 $$\mathrm{An}\:\mathrm{aeroplane}\:\mathrm{leaves}\:\mathrm{a}\:\mathrm{port}\:\mathrm{P}\left(\mathrm{51}°\mathrm{S},\:\:\mathrm{29}°\mathrm{E}\right)\:\mathrm{and} \\ $$$$\mathrm{after}\:\mathrm{flying}\:\mathrm{7597}\:\mathrm{km}\:\mathrm{due}\:\mathrm{north}\:\mathrm{it}\:\mathrm{reached}\: \\ $$$$\mathrm{another}\:\mathrm{port}\:\mathrm{R}.\:\mathrm{calculate}\:\mathrm{the}. \\ $$$$\left(\mathrm{i}\right)\:\mathrm{Latitude}\:\mathrm{of}\:\mathrm{R}\:\mathrm{correct}\:\mathrm{to}\:\mathrm{the}\:\mathrm{nearest}\:\mathrm{degree} \\ $$$$\left(\mathrm{ii}\right)\:\mathrm{Radius}\:\mathrm{of}\:\mathrm{parallel}\:\mathrm{of}\:\mathrm{latitude}\:\mathrm{through}\:\mathrm{R} \\ $$$$\mathrm{to}\:\mathrm{the}\:\mathrm{nearest}\:\mathrm{whole}\:\mathrm{number}. \\ $$ Answered…
Question Number 10155 by Tawakalitu ayo mi last updated on 27/Jan/17 $$\mathrm{solve}\:\mathrm{for}\:\mathrm{x} \\ $$$$\mathrm{sin}\left(\mathrm{x}\right)\:−\:\sqrt{\mathrm{3cos}\left(\mathrm{x}\right)}\:=\:\mathrm{1} \\ $$ Answered by mrW1 last updated on 28/Jan/17 $$\mathrm{sin}\:\left({x}\right)=\mathrm{1}+\sqrt{\mathrm{3cos}\:\left({x}\right)}\geqslant\mathrm{1} \\…
Question Number 75617 by mathocean1 last updated on 13/Dec/19 $$\left.\mathrm{Demonstrate}\:\mathrm{that}\:\forall\:\mathrm{x}\:\in\right]\mathrm{0};\frac{\pi}{\mathrm{2}}\left[\right. \\ $$$$\mathrm{tanx}=\frac{\mathrm{1}−\mathrm{cos}\left(\mathrm{2x}\right)}{\mathrm{sin}\left(\mathrm{2x}\right)} \\ $$ Commented by mind is power last updated on 13/Dec/19 $$\mathrm{use}\:\mathrm{cos}\left(\mathrm{2x}\right)=\mathrm{1}−\mathrm{2sin}^{\mathrm{2}} \left(\mathrm{x}\right)…
Question Number 141110 by Fikret last updated on 15/May/21 $${sin}^{\mathrm{2}} {x}+{sinx}=\frac{\mathrm{4}}{\mathrm{3}}\:\:\:\:\:\:\:,\:\:\:{x}\in\left[\mathrm{0},\pi\right] \\ $$$${equation}\:\:{sum}\:\:{of}\:{roots}\:{in}\:{range}? \\ $$ Answered by MJS_new last updated on 15/May/21 $${s}^{\mathrm{2}} +{s}−\frac{\mathrm{4}}{\mathrm{3}}=\mathrm{0}\wedge−\mathrm{1}\leqslant{s}\leqslant\mathrm{1}\:\Rightarrow\:{s}=−\frac{\mathrm{1}}{\mathrm{2}}+\frac{\sqrt{\mathrm{57}}}{\mathrm{6}} \\…
Question Number 9986 by lepan last updated on 20/Jan/17 $${In}\:\Delta{ABC}\:,{sinA}:{sinB}:{sinC}=\mathrm{5}:\mathrm{7}:\mathrm{8}. \\ $$$${Find}\:\angle{ABC}. \\ $$ Answered by mrW1 last updated on 20/Jan/17 $${sinA}:{sinB}:{sinC}=\mathrm{5}:\mathrm{7}:\mathrm{8} \\ $$$$ \\…