... )2 21 d( Id) 4[9 d( I&apos ;d) ] - = - , ( ) ( )2 22 22 2 2 29a b4 d( I&apos ;d) d( Id) 35 4. 35a b a b - = - = + +0,25Cõu6b1)2 22 22 236a b35 a 36ba b - = = +.Dthyb 0 ạnờnchnb ... - - > - 0.25Cõu7bx 2(x 3)(x 2)x 3 - - - > +0,252x 10(x 3)(x 3) 1 x 10x 10 é > Û - + > Û > Û ê < - ê ë.Do x 3 x 10 > Þ >0,25éPNVHNGDNCHMTHITHéIHCLNI.NM2011.KhiA.I.MụnToỏnCõu1 ... = .Pttd:6x+y6=0,6x+y+6=0.0,25Mtcu(S)cútõmI(213),bk R 3 =Gi(Q)lmtphngsongsongvi(P)vtipxỳcvi(S).Pt(Q): 2x 2y z D 0 + - + =Tacú ( )2.2 2( 1) 3 D D 10 d I,(Q) R 3 D 1 9 D 83 + - - + = ộ...