TM NGHI^E.M T^O'NG QUAT CU'A PHU.O.NG TRNH XY” +Y0− 1XY= 0,KHI BI...

149)

Tm nghi^e.m t^o'ng quat cu'a phu.o.ng trnh

^{xy” +y}

⁰

^{− 1}_x^{y= 0,}

khi bi^et m^o.t nghi^e.m ri^eng co da.ng

^y

¹

^{= a}_x

.

HD gia’i: y

₁

= 1x

la m^o.t nghi^e.m cu'a phu.o.ng trnh. Ta tm nghi^e.m ri^eng

^y

²

^=u(x)1_x^.

Thay vao phu.o.ng trnh ta tm du.o..c

^y

²

^=x.

V^a.y nghi^e.m t^o'ng quat cu'a phu.o.ng trnh

la

y= C

₁

x +C

₂

x.