20.06.2013 Views

pdf (it, 2.898,97 KB, 25/01/13)

pdf (it, 2.898,97 KB, 25/01/13)

pdf (it, 2.898,97 KB, 25/01/13)

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Ω <br />

(0, 0) (x0, z0)<br />

V (x0, z0) =<br />

x0<br />

0<br />

2ex (1 + x2 dx +<br />

)<br />

z0<br />

z <br />

<br />

0<br />

(1 + x 2 0) dz = 2(3 − e −x0 (3 + x0(2 + x0))) + z0(1 + x 2 0).<br />

−2e −x (3 + x(2 + x)) + z(1 + x 2 ) = c, c ∈ R<br />

z = c + e−x2(3 + x(2 + x))<br />

1 + x2 y <br />

y(x) = ±<br />

<br />

1 + x2 c + e−x = ±ex/2<br />

2(3 + x(2 + x))<br />

<br />

1 + x 2<br />

ce x + 2x 2 + 4x + 6 .<br />

c ∈ R<br />

<br />

z = y 1−2 = 1/y y = 1/z <br />

z ′ = − y′<br />

= z − x2<br />

y2 z ′ − z = −x 2 <br />

ke x k ∈ R <br />

ax 2 + bx + c<br />

2ax+b−ax 2 −bx−c = −x 2 a = 1 b−c = 0 2a−b = 0<br />

b = c = 2 z z(x) = ke x + x 2 + 2x + 2 <br />

y <br />

k ∈ R<br />

y(x) =<br />

1<br />

ke x + x 2 + 2x + 2 ,<br />

<br />

<br />

<br />

˙x − 3x − 2y = cos(2t)<br />

˙y − 4x − y = 0<br />

<br />

A =<br />

3 2<br />

4 1<br />

<br />

<br />

cos(2t)<br />

, B(t) =<br />

0<br />

2 ˙y = ¨x − 3 ˙x + 2 sin(2t)<br />

˙y <br />

2(4x + y) = ¨x − 3 ˙x + 2 sin(2t).<br />

¨x − 3 ˙x − 8x − 2y + 2 sin(2t) = 0<br />

2y <br />

<br />

.<br />

¨x − 3 ˙x − 8x − ( ˙x − 3x − cos(2t)) + 2 sin(2t) = 0.<br />

x<br />

<br />

¨x − 3 ˙x − 8x − ˙x + 3x + cos(2t) + 2 sin(2t) = 0.<br />

¨x − 4 ˙x − 5x = −2 sin(2t) − cos(2t).

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!