Menu Close

Category: Algebra

let-Q-1-tan-3pi-8-tan-pi-10-1-tan-pi-8-tan-pi-10-prove-that-Q-1-Q-1-7-3-5-85-38-5-

Question Number 72332 by aliesam last updated on 27/Oct/19 $${let}\:{Q}=\frac{\mathrm{1}+{tan}\left(\frac{\mathrm{3}\pi}{\mathrm{8}}\right)\:.\:{tan}\left(\frac{\pi}{\mathrm{10}}\right)}{\mathrm{1}−{tan}\left(\frac{\pi}{\mathrm{8}}\right).{tan}\left(\frac{\pi}{\mathrm{10}}\right)} \\ $$$$ \\ $$$${prove}\:{that} \\ $$$$\: \\ $$$$\frac{{Q}−\mathrm{1}}{{Q}+\mathrm{1}}=\sqrt{\mathrm{7}−\mathrm{3}\sqrt{\mathrm{5}}−\sqrt{\mathrm{85}−\mathrm{38}\sqrt{\mathrm{5}}}} \\ $$$$ \\ $$ Answered by mind…

What-is-the-probability-that-3-customers-waiting-in-bank-will-be-served-in-sequence-of-their-arrival-

Question Number 6799 by Tawakalitu. last updated on 27/Jul/16 $${What}\:{is}\:{the}\:{probability}\:{that}\:\mathrm{3}\:{customers}\:{waiting}\:{in}\:{bank}\:{will}\: \\ $$$${be}\:{served}\:{in}\:{sequence}\:{of}\:{their}\:{arrival}. \\ $$ Commented by Yozzii last updated on 27/Jul/16 $${sequence}\:{of}\:{arrival}\:{is}\:{one}\:{out}\:{of}\:\mathrm{3}!=\mathrm{6}. \\ $$$$\Rightarrow\:{experimental}\:{probability}=\frac{\mathrm{1}}{\mathrm{6}}. \\…

Question-6791

Question Number 6791 by Tawakalitu. last updated on 26/Jul/16 Commented by Yozzii last updated on 27/Jul/16 $$\frac{\mathrm{2}}{\mathrm{3}}{a}=\frac{\mathrm{3}}{\mathrm{4}}{b}=\frac{\mathrm{5}}{\mathrm{6}}{c}=\frac{\mathrm{6}}{\mathrm{5}}{d}\:\:\:\:\left({a},{b},{c},{d}\in\mathbb{N}\right) \\ $$$$\frac{{a}}{{b}}=\frac{\mathrm{9}}{\mathrm{8}},\:\frac{{b}}{{c}}=\frac{\mathrm{10}}{\mathrm{9}},\:\frac{{c}}{{d}}=\frac{\mathrm{36}}{\mathrm{25}} \\ $$$$\frac{{a}}{{c}}=\frac{{a}}{{b}}×\frac{{b}}{{c}}=\frac{\mathrm{9}}{\mathrm{8}}×\frac{\mathrm{10}}{\mathrm{9}}=\frac{\mathrm{5}}{\mathrm{4}}\Rightarrow{a}=\frac{\mathrm{5}}{\mathrm{4}}{c} \\ $$$${b}=\frac{\mathrm{10}}{\mathrm{9}}{c},\:{d}=\frac{\mathrm{25}}{\mathrm{36}}{c} \\ $$$$…

When-the-price-of-egg-was-raised-by-2-an-egg-the-number-of-eggs-which-can-be-bought-for-120-is-reduced-by-5-What-is-the-present-price-of-the-egg-

Question Number 6792 by Tawakalitu. last updated on 26/Jul/16 $${When}\:{the}\:{price}\:{of}\:{egg}\:\:{was}\:{raised}\:{by}\:#\mathrm{2}\:{an}\:{egg},\:\:{the}\:{number}\:{of}\:{eggs} \\ $$$${which}\:{can}\:{be}\:{bought}\:{for}\:#\mathrm{120}\:{is}\:{reduced}\:{by}\:#\mathrm{5}.\:{What}\:{is}\:{the} \\ $$$${present}\:{price}\:{of}\:{the}\:{egg}. \\ $$ Commented by Yozzii last updated on 27/Jul/16 $${Let}\:{price}\:{per}\:{egg}\:{be}\:{p}={p}_{\mathrm{0}} +\mathrm{2}\:\left({p}_{\mathrm{0}}…

What-is-the-smallest-even-number-greater-than-3-that-cannot-be-expressed-as-the-sum-of-two-prime-numbers-

Question Number 6772 by Tawakalitu. last updated on 24/Jul/16 $${What}\:{is}\:{the}\:{smallest}\:{even}\:{number}\:{greater}\:{than}\:\mathrm{3}\:{that}\:{cannot} \\ $$$${be}\:{expressed}\:{as}\:{the}\:{sum}\:{of}\:{two}\:{prime}\:{numbers}\:? \\ $$ Commented by Yozzii last updated on 24/Jul/16 $${Let}\:{S}\:{be}\:{a}\:{set}\:{of}\:{n}\:{elements},\:{so}\:{that}\:\mid{S}\mid={n}\geqslant\mathrm{4}. \\ $$$${Let}\:{P}\:{be}\:{a}\:{partition}\:{of}\:{S}\:{into}\:{two}\:{sets} \\…