GIA'I PHU.O.NG TRNH

121)

Gia'i phu.o.ng trnh:

^y”−y

⁰

^{−2y= cosx−3 sinx}HD gia’i:

Phu.o.ng trnh da.c tru.ng

^λ

²

^{+λ−2 = 0⇔λ}

¹

^=−2;λ

²

^{= 1}

Nghi^e.m t^o'ng quat:

^y=C

¹

^e

^−2x

^+C

²

^e

^x

Tm nghi^e.m ri^eng da.ng:

(B−3A= 1(A= 0y=Acosx+Bsinx→−A−3B =−3 →B = 1

V^a.y nghi^e.m t^o'ng quat:

^y=C

¹

^e

^−2x

^+C

²

^e

^x

^{+ sinx}