Question Number 133426 by metamorfose last updated on 22/Feb/21 $$\int\lfloor{x}\rfloor{dx}=?… \\ $$ Answered by MJS_new last updated on 22/Feb/21 $$\mathrm{for}\:{a}<{b}:\:\underset{{a}} {\overset{{b}} {\int}}\lfloor{x}\rfloor{dx}=\lfloor{a}\rfloor\underset{{a}} {\overset{\lceil{a}\rceil} {\int}}{dx}+\underset{\lceil{a}\rceil} {\overset{\lfloor{b}\rfloor−\mathrm{1}}…
Question Number 133420 by liberty last updated on 22/Feb/21 $$\mathrm{Let}\:\mathrm{A}\:\mathrm{denote}\:\mathrm{the}\:\mathrm{event}\:\mathrm{of}\:'\mathrm{test}\:\mathrm{positive}' \\ $$$$\mathrm{in}\:\mathrm{a}\:\mathrm{specific}\:\mathrm{experiment},\:\mathrm{and}\:\mathrm{B} \\ $$$$\mathrm{that}\:\mathrm{of}\:'\mathrm{have}\:\mathrm{cancer}'.\:\mathrm{It}\:\mathrm{is}\:\mathrm{known}\:\mathrm{that} \\ $$$$\mathrm{P}\left(\mathrm{B}\right)=\mathrm{0}.\mathrm{005}\:,\:\mathrm{P}\left(\mathrm{A}\mid\mathrm{B}\right)=\:\mathrm{0}.\mathrm{95}\:\mathrm{and}\:\mathrm{P}\left(\overset{−} {\mathrm{A}}\mid\overset{−} {\mathrm{B}}\right)=\:\mathrm{0}.\mathrm{95} \\ $$$$\mathrm{Suppose}\:\mathrm{someone}\:\mathrm{tests}\:\mathrm{positive}\:\mathrm{in} \\ $$$$\mathrm{the}\:\mathrm{experiment}.\:\mathrm{Find}\:\mathrm{the}\:\mathrm{probability}\:\mathrm{that} \\ $$$$\mathrm{he}\:\mathrm{has}\:\mathrm{cancer}\:. \\…
Question Number 133423 by mathlove last updated on 22/Feb/21 Commented by liki last updated on 24/Feb/21 $$\mathrm{what}\:\mathrm{is}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\mathrm{x}\:\mathrm{and}\:\mathrm{y}? \\ $$ Commented by MJS_new last updated on…
Question Number 133419 by liberty last updated on 22/Feb/21 $$\mathrm{Prove}\:\mathrm{the}\:\mathrm{set}\:\left\{\mathrm{1},\mathrm{2},\mathrm{3},…,\mathrm{1989}\right\} \\ $$$$\mathrm{can}\:\mathrm{be}\:\mathrm{expressed}\:\mathrm{as}\:\mathrm{the}\:\mathrm{disjoint} \\ $$$$\mathrm{union}\:\mathrm{of}\:\mathrm{A}_{\mathrm{1}} ,\mathrm{A}_{\mathrm{2}} ,…,\mathrm{A}_{\mathrm{117}} \:\mathrm{such}\:\mathrm{that} \\ $$$$\left(\mathrm{i}\right)\:\mathrm{each}\:\mathrm{A}_{\mathrm{i}} \:\mathrm{contains}\:\mathrm{the}\:\mathrm{same}\:\mathrm{number}\:\mathrm{of}\:\mathrm{elements}\:,\mathrm{and} \\ $$$$\left(\mathrm{ii}\right)\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{all}\:\mathrm{elements}\:\mathrm{of}\:\mathrm{each}\:\mathrm{A}_{\mathrm{i}} \:\mathrm{is} \\ $$$$\mathrm{the}\:\mathrm{same}\:\mathrm{for}\:\mathrm{i}=\mathrm{1},\mathrm{2},\mathrm{3},…,\mathrm{m}…
Question Number 67881 by mr W last updated on 01/Sep/19 $${find}\:{all}\:{x},{y}\:\in{R}\:{such}\:{that} \\ $$$$\left({x}+{yi}\right)^{\mathrm{2019}} ={x}−{yi} \\ $$ Answered by mind is power last updated on 01/Sep/19…
Question Number 2344 by 123456 last updated on 17/Nov/15 $${f}\left({z}\right){e}^{\mathrm{1}−{z}} ={f}\left(\mathrm{1}−{z}\right)\pi^{{z}} \mathrm{sin}\:\left(\pi{z}\right) \\ $$$${f}\left({z}\right)={z}^{\mathrm{2}} ,\Re\left({z}\right)\geqslant\mathrm{1}/\mathrm{2} \\ $$$${f}\left({z}\right)=\mathrm{0},{z}=?? \\ $$ Commented by Yozzi last updated on…
Question Number 133412 by EDWIN88 last updated on 22/Feb/21 $$\mathrm{What}\:\mathrm{are}\:\mathrm{the}\:\mathrm{last}\:\mathrm{two}\:\mathrm{digits}\:\mathrm{of}\:\mathrm{2}^{\mathrm{222}} −\mathrm{1}\:? \\ $$ Answered by liberty last updated on 22/Feb/21 $$\mathrm{2}^{\mathrm{10}} =\mathrm{1024}\equiv\mathrm{24}\:\left(\mathrm{mod}\:\mathrm{100}\right) \\ $$$$\mathrm{2}^{\mathrm{20}} \equiv\mathrm{24}^{\mathrm{2}}…
Question Number 2341 by Rasheed Soomro last updated on 17/Nov/15 $${For}\:{what}\:{conditions} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\left({i}\right)\:{x}^{{y}^{{z}} } <\left({x}^{{y}} \right)^{{z}} \:\:? \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\left({ii}\right)\:{y}^{{x}^{{z}} } <\left({x}^{{y}} \right)^{{z}} \:? \\ $$…
Question Number 2340 by Yozzi last updated on 18/Nov/15 $${Prove}\:{that},\:\forall{m}\in\mathbb{Z}^{+} , \\ $$$$\underset{{r}=\mathrm{1}} {\overset{{m}} {\prod}}\Gamma\left({x}+\frac{{r}−\mathrm{1}}{{m}}\right)={m}^{\frac{\mathrm{1}}{\mathrm{2}}−{mx}} \left(\mathrm{2}\pi\right)^{\frac{{m}−\mathrm{1}}{\mathrm{2}}} \Gamma\left({mx}\right). \\ $$$$\left\{\Gamma\left({x}\right)=\int_{\mathrm{0}} ^{\infty} {t}^{{x}−\mathrm{1}} {e}^{−{t}} {dt},\:{x}>\mathrm{0}\right\} \\ $$…
Question Number 67871 by rrebo5637@gmail.com last updated on 01/Sep/19 $$\mathrm{8}=\mathrm{4x} \\ $$$$\mathrm{x}=? \\ $$ Commented by Prithwish sen last updated on 01/Sep/19 $$\mathrm{2} \\ $$…