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y = xy ′ + f(y ′ )<br />

F (x, y, p) = xp − y + f(p) y ′ = p dy = p dx <br />

∂pF (x, y, p) = x + f ′ (p) x = −f ′ (p) <br />

⎧<br />

⎪⎨ y(p) = −f ′ (p)p + f(p),<br />

⎪⎩<br />

x(p) = −f ′ (p),<br />

x + f ′ (p) = 0 ∇F (x, y, p) = (p, −1, x + f ′ (p)) <br />

p dx − dy + (x + f ′ (p)) dp = 0.<br />

∇F y dy = p dx (x + f ′ (p)) dp = 0 dp = 0<br />

p = c c ∈ R y = cx + f(c) c ∈ R <br />

<br />

y = xf(y ′ ) − g(y ′ ) f(p) = p<br />

f(p) = p <br />

f(p) = p F (x, y, p) = xf(p) − g(p) − y y ′ = p <br />

dy = p dx ∂pF (x, y, p) = xf ′ (p) − g ′ (p) <br />

f ′ (p) = 0 g ′ (p) = 0 f(p) = c1 g(p) = c2<br />

c ∈ R y = c1x − c2 c1, c2 ∈ R f ′ (p) = 0 <br />

⎧⎪ ⎨x<br />

=<br />

⎪⎩<br />

g′ (p)<br />

f ′ (p) ,<br />

y = g′ (p)<br />

f ′ f(p) − g(p).<br />

(p)<br />

xf ′ (p)−g ′ (p) = 0 ∇F (x, y, p) = (f(p), −1, xf ′ (p)−g ′ (p)) <br />

<br />

f(p) dx − dy + (xf ′ (p) − g ′ (p)) dp = 0.<br />

∇F y dy = p dx <br />

(f(p) − p) dx + (xf ′ (p) − g ′ (p)) dp = 0.<br />

f(p) = p<br />

dx<br />

dp + f ′ (p)<br />

f(p) − p x = g′ (p)<br />

f(p) − p ,<br />

x = x(p) x(p, c) c ∈ R<br />

c ∈ R<br />

<br />

x = x(p, c),<br />

y = x(p, c) f(p) − g(p).

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