Վարժ․ 264

ա) 2x3+x2+3

2x3+x2+3/x-1=2x2+3x+3 (6)

2x3+x2+3=(x-1)(2x2+3x+3)+6

բ) x4-2x3+3x2+4x-1

x4-2x3+3x2+4x-1/x-1=x3-x2+4x+8 (7)

x4-2x3+3x2+4x-1=(x-1)(x3-x2+4x+8)+7

գ) 4x3+5x2-3x+2

4x3+5x2-3x+2/x-1=4x2+9x+6 (8)

4x3+5x2-3x+2=(x-1)(4x2+9x+6)+8

դ) x5-3x2+3x-10

x5-3x2+3x-10/x-1=x4+x3-2x2-2x+1 (-9)

x5-3x2+3x-10=(x-1)(x4+x3-2x2-2x+1)-9

Վարժ․ 265

ա) 5x3-3x2+2

(x-1)=> 5-3+2=4

(x+1)= -5-3+2= -6

բ) 2x4-3x3-4x2+5x-6

(x-1)=> 2-3-4+5-6= -6

(x+1)=> 2-(-3)-4+(-5)-6= -10

գ) 3x3+2x2-6x+7

(x-1)=> 3+2-6+7=6

(x+1)=> -3+2-(-6)+7=12

դ) 3x5-4x2-3x+6

(x-1)=> 3-4-3+6=2

(x+1)= -3-4-(-3)+6=2

Վարժ․ 267

ա) x3+2x2-x-2=0

(1; -1; 2; -2)

x3+2x2-x-2/x-1=x2+3x+2

(x-1)(x2+3x+2)=0=> [ x-1=0; x2+3x+2=0=> [ x=1; x2+3x+2=0 (1)

x2+3x+2=0

D=9-8=1

[ x= -3-1/2; x= -3+1/2=> [ x= -4/2; x= -2/2=> [ x= -2; x= -1

(1)=> [ x=1; x= -2; x= -1

Պատ՝․ -2; -1; 1

բ) x3+6x2+11x+6=0

(1; -1; 2; -2; 3; -3; 6; -6)

x3+6x2+11x+6/x+1=x2+5x+6

(x+1)(x2+5x+6)=0=> [ x+1=0; x2+5x+6=0=> [ x= -1; x2+5x+6=0 (1)

x2+5x+6=0

D=25-24=1

[ x= -5-1/2; x= -5+1/2=> [ x= -6/2; x= -4/2=> [ x= -3; x= -2

(1)=> [ x= -1; x= -2; x= -3

Պատ՝․ -1; -2; -3

գ) x3-2x2-2x-3=0

(1; -1; 3; -3)

x3-2x2-2x-3/x-3=x2+x+1

(x-3)(x2+x+1)=0=> [ x-3=0; x2+x+1=0=> [ x=3; x2+x+1=0 (1)

x2+x+1

D=1-4= -3 (Ø)

(1)=> x=3

Պատ՝․ 3

դ) x3+x2-x+2=0

(1; -1; 2; -2)

x3+x2-x+2/x+2=x2-x+1

(x+2)(x2-x+1)=0=> [ x+2=0; x2-x+1=0=> [ x= -2; x2-x+1=0 (1)

x2-x+1=0

D=1-4= -3 (Ø)

(1)=> x= -2

Պատ՝․ -2

ե) x3+2x2-7x+4=0

(1; -1; 2; -2; 4; -4)

x3+2x2-7x+4/x-1=x2+3x-4

(x-1)(x2+3x-4)=0=> [ x-1=0; x2+3x-4=0=> [ x=1; x2+3x-4=0 (1)

x2+3x-4=0

D=9-(-16)=25

[ x= -3-5/2; x= -3+5/2=> [ x= -8/2; x=2/2=> [ x= -4; x=1

(1)=> [ x=1; x= -4

Պատ՝․ 1; -4

զ) x3-5x2+8x-4=0

(1; -1; 2; -2; 4; -4)

x3-5x2+8x-4/x-1=x2-4x+4

(x-1)(x2-4x+4)=0=> [ x-1=0; x2-4x+4=0=> [ x=1; x2-4x+4=0 (1)

x2-4x+4=0

D=16-16=0

x=4/2=2

(1)=> [ x=1; x=2

Պատ՝․ 1; 2