Question Number 74301 by ~blr237~ last updated on 21/Nov/19 $${Prove}\:{that}\:\:{S}=\left\{\left({x},{y},{z}\right)\in\mathbb{R}^{\mathrm{3}} \backslash\:{x}^{\mathrm{2}} +{y}^{\mathrm{2}} ={z}^{\mathrm{2}} \:\right\}\:{is}\:{a}\:{surface}\: \\ $$$${and}\:{find}\:{out}\:{if}\:{possible}\:{the}\:{tangent}\:{plan}\:{in}\:{O}\left(\mathrm{0},\mathrm{0},\mathrm{0}\right). \\ $$ Answered by mind is power last updated…
Question Number 8764 by tawakalitu last updated on 26/Oct/16 $$\left(\mathrm{a}\right)\:\mathrm{Find}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{given}\:\mathrm{by} \\ $$$$\mathrm{S}_{\mathrm{n}} \:=\:\frac{\mathrm{1}}{\mathrm{1}.\mathrm{3}}\:+\:\frac{\mathrm{1}}{\mathrm{3}.\mathrm{5}}\:+\:\frac{\mathrm{1}}{\mathrm{5}.\mathrm{7}}\:+\:…\:+\:\frac{\mathrm{1}}{\left(\mathrm{2n}\:−\:\mathrm{1}\right)\left(\mathrm{2n}\:+\:\mathrm{1}\right)} \\ $$$$\left(\mathrm{b}\right)\:\mathrm{find}\:\mathrm{the}\:\mathrm{limit}\:\mathrm{of}\:\:\:\mathrm{S}_{\mathrm{n}} \:\:\mathrm{as}\:\:\mathrm{n}\:\rightarrow\:\infty \\ $$ Commented by sou1618 last updated on 26/Oct/16…
Question Number 8763 by tawakalitu last updated on 26/Oct/16 $$\int\mathrm{x}\sqrt{\mathrm{3x}\:+\:\mathrm{1}}\:\:\mathrm{dx} \\ $$ Commented by FilupSmith last updated on 26/Oct/16 $${u}=\mathrm{3}{x}+\mathrm{2}\Rightarrow{x}=\frac{\mathrm{1}}{\mathrm{3}}\left({u}−\mathrm{2}\right) \\ $$$${du}=\mathrm{3}{dx} \\ $$$$\frac{\mathrm{1}}{\mathrm{3}}\int\mathrm{3}{x}\sqrt{\mathrm{3}{x}+\mathrm{2}}{dx} \\…
Question Number 8762 by tawakalitu last updated on 26/Oct/16 $$\int\mathrm{x}^{\mathrm{2}} \left(\mathrm{2x}\:+\:\mathrm{1}\right)^{\mathrm{1}/\mathrm{2}} \:\mathrm{dx} \\ $$ Answered by sou1618 last updated on 26/Oct/16 $${I}=\int{x}^{\mathrm{2}} \sqrt{\mathrm{2}{x}+\mathrm{1}}{dx} \\ $$$${t}=\mathrm{2}{x}+\mathrm{1}…
Question Number 8757 by FilupSmith last updated on 26/Oct/16 $$\mathrm{A}\:\mathrm{balloon}\:\mathrm{is}\:\mathrm{inflated}\:\mathrm{such}\:\mathrm{that}\:\mathrm{every} \\ $$$$\mathrm{point}\:\mathrm{expands}\:\mathrm{at}\:{a}\:\mathrm{units}/\mathrm{second}. \\ $$$$ \\ $$$$\mathrm{An}\:\mathrm{ant}\:\mathrm{runs}\:\mathrm{from}\:\mathrm{one}\:\mathrm{point}\:\boldsymbol{{A}}\:\mathrm{to}\:\mathrm{another} \\ $$$$\mathrm{point}\:\boldsymbol{{B}}.\:\mathrm{If}\:\mathrm{the}\:\mathrm{ant}\:\mathrm{moves}\:{b}\:\mathrm{units}/\mathrm{second}, \\ $$$$\mathrm{what}\:\mathrm{will}\:\mathrm{influence}\:\mathrm{if}\:\mathrm{or}\:\mathrm{not}\:\mathrm{the}\:\mathrm{ant}\:\mathrm{will} \\ $$$$\mathrm{ever}\:\mathrm{reach}\:\mathrm{point}\:\boldsymbol{{B}}? \\ $$ Commented…
Question Number 74293 by Mr. K last updated on 21/Nov/19 Commented by Mr. K last updated on 21/Nov/19 $${ABCD}\:{id}\:{a}\:{quadrilateral},\:{cos}\theta=\frac{\sqrt{\mathrm{7}}}{\mathrm{4}}. \\ $$$${AE}=\mathrm{1},\:{BE}=\mathrm{4},\:{CE}=\mathrm{3}\:{and}\:{DE}=\mathrm{2}. \\ $$$${Find}\:{the}\:{area}\:{of}\:{the}\:{quadrilateral}. \\ $$…
Question Number 8756 by trapti rathaur@ gmail.com last updated on 25/Oct/16 $${show}\:{that}\:{every}\:{sphere}\:{through}\:{the}\:{circle}\:{x}^{\mathrm{2}} +{y}^{\mathrm{2}} −\mathrm{2}{ax}+{r}^{\mathrm{2}} =\mathrm{0},{z}=\mathrm{0} \\ $$$$,{z}=\mathrm{0}\:\:\:\:\:\:\:{cuts}\:{orthogonally}\:{every}\:{sphere}\:{through}\:{the}\:{circle}\: \\ $$$${x}^{\mathrm{2}} +{z}^{\mathrm{2}} ={r}^{\mathrm{2}} ,\:{y}={o}\:. \\ $$ Terms…
Question Number 139825 by mathdave last updated on 01/May/21 Commented by mr W last updated on 01/May/21 $${rate}\:{of}\:{changing}\:{of}\:{distance}\:{is}\:{the} \\ $$$${sum}\:{of}\:{the}\:{speeds}\:{of}\:{the}\:{cars}: \\ $$$${case}\:\mathrm{1}: \\ $$$$−\left(\mathrm{50}+\mathrm{40}\right)=−\mathrm{90}\:{km}/{h}\:{if}\:{A}\:{was}\:{to} \\…
Question Number 8755 by trapti rathaur@ gmail.com last updated on 25/Oct/16 $${find}\:{the}\:{equation}\:{of}\:{the}\:{sphere}\:{which}\:{touches}\:{the}\:{plane}\: \\ $$$$\mathrm{3}{x}+\mathrm{2}{y}−{z}+\mathrm{2}=\mathrm{0}\:{at}\:{the}\:{point}\:\left(\mathrm{1},−\mathrm{2},\mathrm{1}\right)\:{and}\:{cuts}\:{orthogonally}\:{the} \\ $$$${the}\:{sphere}\:{x}^{\mathrm{2}} +{y}^{\mathrm{2}} +{z}^{\mathrm{2}} −\mathrm{4}{x}+\mathrm{6}{y}+\mathrm{4}=\mathrm{0} \\ $$ Terms of Service Privacy…
Question Number 139824 by mathsuji last updated on 01/May/21 $${Solve}\:{in}\:\mathbb{R}\:{the}\:{following}\:{equation}: \\ $$$$\mathrm{2}\centerdot\mathrm{3}^{{x}} +\mathrm{5}\centerdot\mathrm{4}^{{x}} =\mathrm{4}\centerdot\mathrm{5}^{{x}} +\mathrm{3}\centerdot\mathrm{2}^{{x}} \\ $$ Answered by MJS_new last updated on 02/May/21 $$\mathrm{obviously}\:{x}=\mathrm{0}\vee{x}=\mathrm{1}…