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Category: Geometry

Question-174763

Question Number 174763 by dragan91 last updated on 10/Aug/22 Answered by a.lgnaoui last updated on 11/Aug/22 $$\angle{ADF} \\ $$$$\frac{\mathrm{sin}\:\mathrm{A}}{\mathrm{DF}}=\frac{\mathrm{sin}\:\mathrm{F}}{\mathrm{AD}}=\frac{\mathrm{sin}\:\mathrm{D}}{\mathrm{24}}\:\:\:\:\:\:\left(\mathrm{1}\right) \\ $$$$\angle{EBF} \\ $$$$\frac{\mathrm{sin}\:\mathrm{B}}{\mathrm{x}}=\frac{\mathrm{sin}\:\mathrm{F}}{\mathrm{3}}=\frac{\mathrm{sin}\:\mathrm{E}}{\mathrm{8}}\:\:\:\:\:\:\:\left(\mathrm{2}\right) \\ $$$$\angle{CDE}…

Question-43621

Question Number 43621 by ajfour last updated on 12/Sep/18 Commented by math1967 last updated on 13/Sep/18 $${AD}=\sqrt{{x}^{\mathrm{2}} −\mathrm{1}}\:\:\:,{AC}=\sqrt{{x}^{\mathrm{2}} +{x}^{\mathrm{2}} −\mathrm{1}}=\sqrt{\mathrm{2}{x}^{\mathrm{2}} −\mathrm{1}} \\ $$$$\bigtriangleup{ABD}\sim\bigtriangleup{CED}\:\therefore\frac{{ED}}{{x}}=\frac{\mathrm{1}}{\:\sqrt{{x}^{\mathrm{2}} −\mathrm{1}}} \\…

Question-174664

Question Number 174664 by dragan91 last updated on 07/Aug/22 Answered by mr W last updated on 07/Aug/22 $$\frac{{b}−\mathrm{5}}{\mathrm{5}}=\frac{\mathrm{5}}{{a}−\mathrm{5}} \\ $$$$\Rightarrow{ab}=\mathrm{5}\left({a}+{b}\right) \\ $$$${let}\:{u}={a}+{b},\:{v}={ab} \\ $$$$\Rightarrow{v}=\mathrm{5}{u} \\…

found-something-others-have-found-before-which-I-thought-might-be-of-interest-especially-for-Sir-Tanmay-Chaudhury-take-any-polynome-of-degree-4-with-2-real-inflection-points-y-ax-4-bx-3-cx-2-dx

Question Number 43461 by MJS last updated on 10/Sep/18 $$\mathrm{found}\:\mathrm{something}\:\left(\mathrm{others}\:\mathrm{have}\:\mathrm{found}\:\mathrm{before}\right) \\ $$$$\mathrm{which}\:\mathrm{I}\:\mathrm{thought}\:\mathrm{might}\:\mathrm{be}\:\mathrm{of}\:\mathrm{interest}, \\ $$$$\mathrm{especially}\:\mathrm{for}\:\mathrm{Sir}\:\mathrm{Tanmay}\:\mathrm{Chaudhury}: \\ $$$$\mathrm{take}\:\mathrm{any}\:\mathrm{polynome}\:\mathrm{of}\:\mathrm{degree}\:\mathrm{4}\:\mathrm{with}\:\mathrm{2}\:\mathrm{real} \\ $$$$\mathrm{inflection}\:\mathrm{points} \\ $$$${y}={ax}^{\mathrm{4}} +{bx}^{\mathrm{3}} +{cx}^{\mathrm{2}} +{dx}+{e} \\ $$$${y}''=\mathrm{12}{ax}^{\mathrm{2}}…