Menu Close

Author: Tinku Tara

x-n-cos-nx-dx-

Question Number 152186 by Tawa11 last updated on 26/Aug/21 $$\int\mathrm{x}^{\mathrm{n}} \:\mathrm{cos}\left(\mathrm{nx}\right)\:\mathrm{dx} \\ $$ Answered by mindispower last updated on 26/Aug/21 $${nx}={y} \\ $$$$\Leftrightarrow\frac{\mathrm{1}}{{n}^{{n}+\mathrm{1}} }\int{y}^{{n}} {cos}\left({x}\right){dx}…

A-ball-is-bouncing-elastically-with-a-speed-1-m-s-between-walls-of-a-railway-compartment-of-size-10-m-in-a-direction-perpendicular-to-walls-The-train-is-moving-at-a-constant-velocity-of-10-m-s-parall

Question Number 21112 by Tinkutara last updated on 13/Sep/17 $$\mathrm{A}\:\mathrm{ball}\:\mathrm{is}\:\mathrm{bouncing}\:\mathrm{elastically}\:\mathrm{with}\:\mathrm{a} \\ $$$$\mathrm{speed}\:\mathrm{1}\:\mathrm{m}/\mathrm{s}\:\mathrm{between}\:\mathrm{walls}\:\mathrm{of}\:\mathrm{a}\:\mathrm{railway} \\ $$$$\mathrm{compartment}\:\mathrm{of}\:\mathrm{size}\:\mathrm{10}\:\mathrm{m}\:\mathrm{in}\:\mathrm{a}\:\mathrm{direction} \\ $$$$\mathrm{perpendicular}\:\mathrm{to}\:\mathrm{walls}.\:\mathrm{The}\:\mathrm{train}\:\mathrm{is} \\ $$$$\mathrm{moving}\:\mathrm{at}\:\mathrm{a}\:\mathrm{constant}\:\mathrm{velocity}\:\mathrm{of}\:\mathrm{10}\:\mathrm{m}/\mathrm{s} \\ $$$$\mathrm{parallel}\:\mathrm{to}\:\mathrm{the}\:\mathrm{direction}\:\mathrm{of}\:\mathrm{motion}\:\mathrm{of} \\ $$$$\mathrm{the}\:\mathrm{ball}.\:\mathrm{As}\:\mathrm{seen}\:\mathrm{from}\:\mathrm{the}\:\mathrm{ground} \\ $$$$\left({a}\right)\:\mathrm{the}\:\mathrm{direction}\:\mathrm{of}\:\mathrm{motion}\:\mathrm{of}\:\mathrm{the}\:\mathrm{ball} \\…

STATEMENT-1-z-1-2-z-2-2-z-3-2-z-4-2-0-where-z-1-z-2-z-3-and-z-4-are-the-fourth-roots-of-unity-and-STATEMENT-2-1-1-4-cos0-i-sin0-1-4-

Question Number 21111 by Tinkutara last updated on 13/Sep/17 $$\mathrm{STATEMENT}-\mathrm{1}\::\:{z}_{\mathrm{1}} ^{\mathrm{2}} \:+\:{z}_{\mathrm{2}} ^{\mathrm{2}} \:+\:{z}_{\mathrm{3}} ^{\mathrm{2}} \:+\:{z}_{\mathrm{4}} ^{\mathrm{2}} \:= \\ $$$$\mathrm{0}\:\mathrm{where}\:{z}_{\mathrm{1}} ,\:{z}_{\mathrm{2}} ,\:{z}_{\mathrm{3}} \:\mathrm{and}\:{z}_{\mathrm{4}} \:\mathrm{are}\:\mathrm{the}\:\mathrm{fourth} \\…

STATEMENT-1-The-locus-of-z-if-arg-z-1-z-1-pi-2-is-a-circle-and-STATEMENT-2-z-2-z-2-pi-2-then-the-locus-of-z-is-a-circle-

Question Number 21109 by Tinkutara last updated on 13/Sep/17 $$\mathrm{STATEMENT}-\mathrm{1}\::\:\mathrm{The}\:\mathrm{locus}\:\mathrm{of}\:{z},\:\mathrm{if} \\ $$$$\mathrm{arg}\left(\frac{{z}\:−\:\mathrm{1}}{{z}\:+\:\mathrm{1}}\right)\:=\:\frac{\pi}{\mathrm{2}}\:\mathrm{is}\:\mathrm{a}\:\mathrm{circle}. \\ $$$$\boldsymbol{\mathrm{and}} \\ $$$$\mathrm{STATEMENT}-\mathrm{2}\::\:\mid\frac{{z}\:−\:\mathrm{2}}{{z}\:+\:\mathrm{2}}\mid\:=\:\frac{\pi}{\mathrm{2}},\:\mathrm{then} \\ $$$$\mathrm{the}\:\mathrm{locus}\:\mathrm{of}\:{z}\:\mathrm{is}\:\mathrm{a}\:\mathrm{circle}. \\ $$ Commented by youssoufab last updated…

Let-A-B-C-be-three-sets-of-complex-numbers-as-defined-below-A-z-Im-z-1-B-z-z-2-i-3-C-z-Re-1-i-z-2-Let-z-be-any-point-in-A-B-C-and-let-w-be-any-point-satisfy

Question Number 21108 by Tinkutara last updated on 13/Sep/17 $$\mathrm{Let}\:{A},\:{B},\:{C}\:\mathrm{be}\:\mathrm{three}\:\mathrm{sets}\:\mathrm{of}\:\mathrm{complex} \\ $$$$\mathrm{numbers}\:\mathrm{as}\:\mathrm{defined}\:\mathrm{below} \\ $$$${A}\:=\:\left\{{z}\::\:\mathrm{Im}\:{z}\:\geqslant\:\mathrm{1}\right\} \\ $$$${B}\:=\:\left\{{z}\::\:\mid{z}\:−\:\mathrm{2}\:−\:{i}\mid\:=\:\mathrm{3}\right\} \\ $$$${C}\:=\:\left\{{z}\::\:\mathrm{Re}\left(\left(\mathrm{1}\:−\:{i}\right){z}\right)\:=\:\sqrt{\mathrm{2}}\right\}. \\ $$$$\mathrm{Let}\:{z}\:\mathrm{be}\:\mathrm{any}\:\mathrm{point}\:\mathrm{in}\:{A}\:\cap\:{B}\:\cap\:{C}\:\mathrm{and}\:\mathrm{let} \\ $$$${w}\:\mathrm{be}\:\mathrm{any}\:\mathrm{point}\:\mathrm{satisfying}\:\mid{w}\:−\:\mathrm{2}\:−\:{i}\mid\:< \\ $$$$\mathrm{3}.\:\mathrm{Then},\:\mid{z}\mid\:−\:\mid{w}\mid\:+\:\mathrm{3}\:\mathrm{lies}\:\mathrm{between} \\…

Solve-the-differential-equations-i-x-2-d-2-y-dx-2-x-dy-dx-y-log-x-ii-x-2-2-d-2-y-dx-2-4-x-2-dy-dx-6y-x-

Question Number 86640 by niroj last updated on 29/Mar/20 $$\:\boldsymbol{\mathrm{Solve}}\:\boldsymbol{\mathrm{the}}\:\:\boldsymbol{\mathrm{differential}}\:\boldsymbol{\mathrm{equations}}: \\ $$$$\:\:\left(\boldsymbol{\mathrm{i}}\right).\boldsymbol{\mathrm{x}}^{\mathrm{2}} \:\frac{\boldsymbol{\mathrm{d}}^{\mathrm{2}} \boldsymbol{\mathrm{y}}}{\boldsymbol{\mathrm{dx}}^{\mathrm{2}} }\:−\:\boldsymbol{\mathrm{x}}\frac{\boldsymbol{\mathrm{dy}}}{\boldsymbol{\mathrm{dx}}}\:+\:\boldsymbol{\mathrm{y}}\:=\:\:\boldsymbol{\mathrm{log}}\:\boldsymbol{\mathrm{x}}. \\ $$$$\:\:\left(\boldsymbol{\mathrm{ii}}\right).\:\left(\boldsymbol{\mathrm{x}}+\mathrm{2}\right)^{\mathrm{2}} \:\frac{\boldsymbol{\mathrm{d}}^{\mathrm{2}} \boldsymbol{\mathrm{y}}}{\boldsymbol{\mathrm{dx}}^{\mathrm{2}} }\:−\:\mathrm{4}\left(\boldsymbol{\mathrm{x}}+\mathrm{2}\right)\frac{\boldsymbol{\mathrm{dy}}}{\boldsymbol{\mathrm{dx}}}\:+\:\mathrm{6}\boldsymbol{\mathrm{y}}\:=\:\:\boldsymbol{\mathrm{x}}. \\ $$$$\: \\ $$ Answered…

Solve-the-system-y-x-x-y-x-y-x-y-xy-Find-all-the-real-solutions-other-than-x-0-and-y-0-

Question Number 152178 by mathdanisur last updated on 26/Aug/21 $$\mathrm{Solve}\:\mathrm{the}\:\mathrm{system} \\ $$$$\begin{cases}{\mathrm{y}\sqrt{\mathrm{x}}\:+\:\mathrm{x}\sqrt{\mathrm{y}}\:=\:\mathrm{x}\:+\:\mathrm{y}}\\{\sqrt{\mathrm{x}}\:+\:\sqrt{\mathrm{y}}\:=\:\mathrm{xy}}\end{cases} \\ $$$$\mathrm{Find}\:\mathrm{all}\:\mathrm{the}\:\mathrm{real}\:\mathrm{solutions}\:\mathrm{other}\:\mathrm{than} \\ $$$$\mathrm{x}\:=\:\mathrm{0}\:\:\mathrm{and}\:\:\mathrm{y}\:=\:\mathrm{0} \\ $$ Commented by john_santu last updated on 26/Aug/21…