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Category: Differential Equation

4x-2-y-y-0-x-gt-0-

Question Number 103037 by bramlex last updated on 12/Jul/20 $$\mathrm{4x}^{\mathrm{2}} \mathrm{y}''\:+\mathrm{y}\:=\:\mathrm{0}\:,\:\mathrm{x}\:>\:\mathrm{0} \\ $$ Answered by maths mind last updated on 12/Jul/20 $${let}\:{y}={x}^{{t}} \\ $$$$\Rightarrow\mathrm{4}{x}^{\mathrm{2}} \left({t}\left({t}−\mathrm{1}\right)\right){x}^{{t}−\mathrm{2}}…

y-x-y-1-x-y-1-

Question Number 102840 by Dwaipayan Shikari last updated on 11/Jul/20 $${y}'+\sqrt{{x}+{y}−\mathrm{1}}={x}+{y}+\mathrm{1} \\ $$ Answered by OlafThorendsen last updated on 12/Jul/20 $${y}\:=\:\mathrm{Y}^{\mathrm{2}} −{x}+\mathrm{1} \\ $$$$\mathrm{2Y}'\mathrm{Y}−\mathrm{1}+\sqrt{\mathrm{Y}^{\mathrm{2}} }\:=\:\mathrm{Y}^{\mathrm{2}}…

y-x-x-x-y-

Question Number 168276 by Florian last updated on 07/Apr/22 $$\:\:\:\:{y}\:=\:\sqrt{{x}+\sqrt{{x}+\sqrt{{x}}}} \\ $$$$\:\:\:\:{y}'\:=\: \\ $$$$\:\:\:\:\: \\ $$ Commented by cortano1 last updated on 07/Apr/22 $$\:{y}'=\frac{\mathrm{1}+\frac{\mathrm{1}+\frac{\mathrm{1}}{\mathrm{2}\sqrt{{x}}}}{\mathrm{2}\sqrt{{x}+\sqrt{{x}}}}}{\mathrm{2}\sqrt{{x}+\sqrt{{x}+\sqrt{{x}}}}} \\…

y-3y-10y-14e-5x-

Question Number 102716 by Ar Brandon last updated on 10/Jul/20 $$\mathrm{y}''+\mathrm{3y}'−\mathrm{10y}=\mathrm{14e}^{−\mathrm{5x}} \\ $$ Answered by bramlex last updated on 10/Jul/20 $$\mathrm{Homogenous}\: \\ $$$$\mathrm{r}^{\mathrm{2}} +\mathrm{3r}−\mathrm{10}=\mathrm{0}\:\Rightarrow\left(\mathrm{r}+\mathrm{5}\right)\left(\mathrm{r}−\mathrm{2}\right)=\mathrm{0} \\…

dy-dx-2xy-6y-e-y-2-

Question Number 102639 by bobhans last updated on 10/Jul/20 $$\frac{{dy}}{{dx}}\:−\mathrm{2}{xy}\:=\:\mathrm{6}{y}\:{e}^{{y}^{\mathrm{2}} } \\ $$ Answered by Ar Brandon last updated on 10/Jul/20 $$\mathrm{Let}\:\mathrm{y}=\mathrm{vx}\:\Rightarrow\frac{\mathrm{dy}}{\mathrm{dx}}=\mathrm{v}+\mathrm{x}\frac{\mathrm{dv}}{\mathrm{dx}} \\ $$$$\Rightarrow\:\mathrm{v}+\mathrm{x}\frac{\mathrm{dv}}{\mathrm{dx}}−\mathrm{2vx}^{\mathrm{2}} =\mathrm{6vxe}^{\mathrm{v}^{\mathrm{2}}…

2y-y-y-cos-3x-

Question Number 102527 by bemath last updated on 09/Jul/20 $$\mathrm{2}{y}''−{y}'+{y}\:=\:\mathrm{cos}\:\mathrm{3}{x}\: \\ $$ Answered by Ar Brandon last updated on 09/Jul/20 $$\mathrm{Let}\:\mathrm{y}=\mathrm{acos3x}+\mathrm{bsin3x} \\ $$$$\Rightarrow\mathrm{y}'=−\mathrm{3asin3x}+\mathrm{3bcos3x}\:,\:\mathrm{y}''=−\mathrm{9acos3x}−\mathrm{9bsin3x} \\ $$$$\Rightarrow−\mathrm{2}×\mathrm{9}\left(\mathrm{acos3x}+\mathrm{bsin3x}\right)−\mathrm{3}\left(\mathrm{bcos3x}−\mathrm{asin3x}\right)+\mathrm{acos3x}+\mathrm{bsin3x}…