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karush
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2.2.13 (a) find initial value (b)plot and (c) interval
(a) find initial value (b)plot and (c) interval
$$\displaystyle
y^{\prime}=2x/(y+x^2y), \quad y(0)=-2$$
separate the variables
$$\frac{dy}{dx}=\frac{2x}{y+x^2y}=\frac{2x}{y(1-x^2)}$$
$$y\, dy =\frac{2x}{(1-x^2)}dx$$
integrate
$$\int y\, dy = -\sqrt{4}\int \frac{x}{(1-x^2)} \, dx$$
$$\frac{y^2}{2}= -2\frac{\ln(1 - x^2)}{2}$$
$$y=-\sqrt{4}\sqrt{\ln(1-x^2)}$$ok I am stuck again.,...book answer
$$(a)\, y = −[2 ln(1 + x^2) + 4]^{-1/2} \\ (c) −\infty < x <\infty$$
2.2.13 (a) find initial value (b)plot and (c) interval
(a) find initial value (b)plot and (c) interval
$$\displaystyle
y^{\prime}=2x/(y+x^2y), \quad y(0)=-2$$
separate the variables
$$\frac{dy}{dx}=\frac{2x}{y+x^2y}=\frac{2x}{y(1-x^2)}$$
$$y\, dy =\frac{2x}{(1-x^2)}dx$$
integrate
$$\int y\, dy = -\sqrt{4}\int \frac{x}{(1-x^2)} \, dx$$
$$\frac{y^2}{2}= -2\frac{\ln(1 - x^2)}{2}$$
$$y=-\sqrt{4}\sqrt{\ln(1-x^2)}$$ok I am stuck again.,...book answer
$$(a)\, y = −[2 ln(1 + x^2) + 4]^{-1/2} \\ (c) −\infty < x <\infty$$
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