x p 2 + 2 y p + x = 0 2 y = − x p − x p 2 d y d x = − p − 1 p − x d p d x + x p 2 d p d x 3 p 2 + 1 p = x ( 1 − p 2 ) p 2 d p d x ( 1 − p 2 ) p ( 3 p 2 + 1 ) d p = d x x ∫ ( 1 − p 2 ) p ( 3 p 2 + 1 ) d p = ∫ d x x l n p − 2 3 l n ( 3 p 2 + 1 ) = l n x p 9 p 4 + 6 p 2 + 1 3 = x 9 x 3 p 4 − p 3 + 6 x 3 p 2 + x 3 = 0 xp^2+2yp+x = 0\\
2y = -xp - \dfrac{x}{p}\\
2\dfrac{dy}{dx} = -p -\dfrac{1}{p} -x\dfrac{dp}{dx}+\dfrac{x}{p^2}\dfrac{dp}{dx}\\
\dfrac{3p^2+1}{p} = \dfrac{x(1-p^2)}{p^2}\dfrac{dp}{dx}\\
\dfrac{(1-p^2)}{p(3p^2+1)}dp = \dfrac{dx}{x}\\
\int \dfrac{(1-p^2)}{p(3p^2+1)}dp =\int \dfrac{dx}{x}\\
lnp -\dfrac{2}{3}ln(3p^2+1) = lnx\\
\dfrac{p}{\sqrt[3]{9p^4+6p^2+1}} = x\\
9x^3p^4-p^3+6x^3p^2+x^3=0 x p 2 + 2 y p + x = 0 2 y = − x p − p x 2 d x d y = − p − p 1 − x d x d p + p 2 x d x d p p 3 p 2 + 1 = p 2 x ( 1 − p 2 ) d x d p p ( 3 p 2 + 1 ) ( 1 − p 2 ) d p = x d x ∫ p ( 3 p 2 + 1 ) ( 1 − p 2 ) d p = ∫ x d x l n p − 3 2 l n ( 3 p 2 + 1 ) = l n x 3 9 p 4 + 6 p 2 + 1 p = x 9 x 3 p 4 − p 3 + 6 x 3 p 2 + x 3 = 0
is an implicit solution of the question because it is impossible to express p straightforward in terms of y.
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