Question Number 31953 by 24444355 last updated on 17/Mar/18 $$\mathrm{If}\:{a},\:{b},\:{c},\:{d}\:\mathrm{are}\:\mathrm{in}\:\mathrm{GP},\:\mathrm{then}\:\left({a}^{\mathrm{3}} +{b}^{\mathrm{3}} \right)^{−\mathrm{1}} ,\: \\ $$$$\left({b}^{\mathrm{3}} +{c}^{\mathrm{3}} \right)^{−\mathrm{1}} ,\:\left({c}^{\mathrm{3}} +{a}^{\mathrm{3}} \right)^{−\mathrm{1}} \:\mathrm{are}\:\mathrm{in} \\ $$ Commented by…
Question Number 31952 by 24444355 last updated on 17/Mar/18 $$\mathrm{For}\:\mathrm{a}\:\mathrm{sequence}\:<\:{a}_{{n}} \:>\:\:,\:{a}_{\mathrm{1}} =\:\mathrm{2}\:\mathrm{and}\: \\ $$$$\frac{{a}_{{n}+\mathrm{1}} }{{a}_{{n}} }\:=\:\frac{\mathrm{1}}{\mathrm{3}}\:\:.\:\:\mathrm{Then}\:\underset{{r}=\mathrm{1}} {\overset{\mathrm{20}} {\sum}}\:{a}_{{r}} \:\mathrm{is} \\ $$ Commented by abdo imad…
Question Number 31564 by akhilesh2684894@gmail.com last updated on 10/Mar/18 $$\mathrm{If}\:{f}\left({x}\right)\:\mathrm{and}\:\:{g}\left({x}\right)\:\mathrm{are}\:\mathrm{two}\:\mathrm{integrable} \\ $$$$\mathrm{functions}\:\mathrm{defined}\:\mathrm{on}\:\left[{a},\:{b}\right],\:\mathrm{then} \\ $$$$\mid\:\underset{{a}} {\overset{{b}} {\int}}\:{f}\left({x}\right)\:{g}\left({x}\right)\:{dx}\:\mid\:\:\:\mathrm{is} \\ $$ Commented by MJS last updated on 10/Mar/18…
Question Number 31538 by akhilesh2684894@gmail.com last updated on 09/Mar/18 $$\mathrm{If}\:{f}\left({x}\right)=\:{a}\:{e}^{\mathrm{2}{x}} +{b}\:{e}^{{x}} +{cx}\:\mathrm{satisfies}\:\mathrm{the} \\ $$$$\mathrm{condition}\:{f}\left(\mathrm{0}\right)=\:−\mathrm{1},\:{f}\:'\left(\mathrm{log}\:\mathrm{2}\right)=\mathrm{31}, \\ $$$$\:\underset{\:\mathrm{0}} {\overset{\mathrm{log}\:\mathrm{4}} {\int}}\left({f}\left({x}\right)−{cx}\right)\:{dx}\:=\:\frac{\mathrm{39}}{\mathrm{2}},\:\mathrm{then} \\ $$ Answered by MJS last updated…
Question Number 96845 by DELETED last updated on 05/Jun/20 $$\mathrm{If}\:\mathrm{sin}^{−\mathrm{1}} \frac{{x}}{\mathrm{5}}\:+\:\mathrm{cosec}^{−\mathrm{1}} \frac{\mathrm{5}}{\mathrm{4}}\:=\:\frac{\pi}{\mathrm{2}},\:\mathrm{then}\:{x}= \\ $$ Answered by Sourav mridha last updated on 05/Jun/20 $$\Rightarrow\mathrm{sin}^{−\mathrm{1}} \left(\frac{\boldsymbol{{x}}}{\mathrm{5}}\right)=\mathrm{cos}^{−\mathrm{1}} \left(\frac{\mathrm{4}}{\mathrm{5}}\right)=\mathrm{sin}^{−\mathrm{1}}…
Question Number 31255 by Tip Top last updated on 04/Mar/18 $$\mathrm{2}{n}\:\mathrm{boys}\:\mathrm{are}\:\mathrm{randomly}\:\mathrm{divided}\:\mathrm{into}\:\mathrm{two} \\ $$$$\mathrm{subgroups}\:\mathrm{containing}\:{n}\:\mathrm{boys}\:\mathrm{each}.\:\mathrm{The} \\ $$$$\mathrm{probability}\:\mathrm{that}\:\mathrm{the}\:\mathrm{two}\:\mathrm{tallest}\:\mathrm{boys}\:\mathrm{are} \\ $$$$\mathrm{in}\:\mathrm{different}\:\mathrm{groups}\:\mathrm{is} \\ $$ Answered by MJS last updated on…
Question Number 30939 by paddu1234 last updated on 01/Mar/18 $$\mathrm{If}\:\:{x}^{\mathrm{2}} +{y}^{\mathrm{2}} +{z}^{\mathrm{2}} =\:{r}^{\mathrm{2}} \:,\:\mathrm{then} \\ $$$$\mathrm{tan}^{−\mathrm{1}} \left(\frac{{xy}}{{zr}}\right)+\mathrm{tan}^{−\mathrm{1}} \left(\frac{{yz}}{{xr}}\right)+\mathrm{tan}^{−\mathrm{1}} \left(\frac{{xz}}{{yr}}\right)\:= \\ $$ Answered by ajfour last…
Question Number 95985 by mpym last updated on 29/May/20 $$\mathrm{A}\:\mathrm{and}\:\mathrm{B}\:\mathrm{can}\:\mathrm{complete}\:\mathrm{a}\:\mathrm{piece}\:\mathrm{of}\:\mathrm{work}\:\mathrm{in} \\ $$$$\mathrm{12}\:\mathrm{days}\:\mathrm{and}\:\mathrm{24}\:\mathrm{days}\:\mathrm{respectively}.\:\mathrm{After} \\ $$$$\mathrm{A}\:\mathrm{had}\:\mathrm{worked}\:\mathrm{for}\:\mathrm{6}\:\mathrm{days},\:\mathrm{B}\:\mathrm{joined}\:\mathrm{him}, \\ $$$$\mathrm{and}\:\mathrm{then}\:\mathrm{they}\:\mathrm{completed}\:\mathrm{the}\:\mathrm{work}.\:\mathrm{How} \\ $$$$\mathrm{much}\:\mathrm{should}\:\:\mathrm{A}\:\mathrm{receive}\:\mathrm{as}\:\mathrm{his}\:\mathrm{share}\:\mathrm{from} \\ $$$$\mathrm{the}\:\mathrm{total}\:\mathrm{amount}\:\mathrm{of}\:\mathrm{Rs}.\:\mathrm{180}\:\mathrm{paid}\:\mathrm{for} \\ $$$$\mathrm{completing}\:\mathrm{the}\:\mathrm{work}? \\ $$ Answered…
Question Number 95986 by mpym last updated on 29/May/20 $$\mathrm{In}\:\mathrm{a}\:\mathrm{set}\:\mathrm{of}\:\mathrm{3}\:\mathrm{consecutive}\:\mathrm{natural}\:\mathrm{numbers} \\ $$$$\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{the}\:\mathrm{last}\:\mathrm{2}\:\mathrm{numbers}\:\mathrm{is}\:\mathrm{equal} \\ $$$$\mathrm{to}\:\mathrm{3}\:\mathrm{times}\:\mathrm{the}\:\mathrm{first}\:\mathrm{numbers}.\:\mathrm{Find}\:\mathrm{the} \\ $$$$\mathrm{sum}\:\mathrm{of}\:\mathrm{all}\:\mathrm{the}\:\mathrm{three}\:\mathrm{numbers}. \\ $$ Commented by mr W last updated on…
Question Number 95982 by mpym last updated on 29/May/20 $$\Sigma{x}\left({y}^{\mathrm{3}} −{z}^{\mathrm{3}} \right)=\_\_\_\_\_. \\ $$ Answered by mr W last updated on 29/May/20 $$={x}\left({y}^{\mathrm{3}} −{z}^{\mathrm{3}} \right)+{y}\left({z}^{\mathrm{3}}…