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Problems in Mathematical Analysis.pdf - pwp.net.ipl.pt

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350_Differential Equations_[C/i. 9<br />

we get<br />

Solution. Solv<strong>in</strong>g the homogeneous equation<br />

Hence, it may be taken that<br />

*ir+if'=o f<br />

y l = \nx and # 2 = 1<br />

and the solution of equation (4) may be sought<br />

<strong>in</strong> the form<br />

Form<strong>in</strong>g the system (3) and tak<strong>in</strong>g <strong>in</strong>to account that the reduced form of<br />

the equation (4) is t/"+~ = jt, we obta<strong>in</strong><br />

Whence<br />

and, consequently,<br />

+ >l and<br />

y =<br />

where A and B are arbitrary constants.<br />

2968. Test the follow<strong>in</strong>g systems<br />

tionships:<br />

a) x, x + 1; e) *, x\ x'\<br />

2<br />

b) x , 2x 2<br />

; f) e* 9 e 2<br />

*, e**\<br />

(5)<br />

of functions for l<strong>in</strong>ear rela-<br />

c) 0, 1, x\ g) s<strong>in</strong> *, cos A:, 1;<br />

2<br />

s<strong>in</strong> x, cos 2<br />

*, 1.<br />

d) x, x+1, x +2; h)<br />

2969. Form a l<strong>in</strong>ear homogeneous differential equation, know-<br />

<strong>in</strong>g its fundamental system of equations:<br />

s<strong>in</strong> x, y2 = cos x\<br />

a) y l =<br />

b) y^e*. y 2 ==xe*\<br />

c) y^x* #2 = * 2<br />

<<br />

d) = ^<br />

f/, x<br />

y* = ^ x s<strong>in</strong> ^, = f/ ^ cos A:.<br />

8<br />

2970. Know<strong>in</strong>g the fundamental system of solutions of a l<strong>in</strong>ear<br />

homogeneous differential equation<br />

f<strong>in</strong>d its particular solution y that satisfies the <strong>in</strong>itial conditions

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