Question

Tìm nghiệm:
  a,  \(x^2-3x+2_{ }\)
  b, \(2x^2-5x+3\) 
  c, \(x^2+6x+10\) 
  d, \(x^3-x^2-4x+4\)

Answer 1

a)pt<=>(x-2)(x-1)=0

b)<=>(x-1)(2x-3)=0

c)\(pt\Leftrightarrow\left(x+3\right)^2+1>0\)

d)\(\left(x-2\right)\left(x-1\right)\left(x+2\right)=0\)

mk pt hộ bn r` đấy, h thì quá dễ

Answer 2

a, x^2-3x+2

=x^2-x-2x+2

=x(x-1)-2(x-1)

=(x-1)(x-2)

PT : (x-1)(x-2)=0

=> Nghiem cua PT : x=1 va x=2

b, 2x^2-5x+3

=2x^2-2x-3x+3

=2x(x-1)-3(x-1)

=(2x-3)(x-1)

PT : (2x-3)(x-1)=0

Vay nghiem cua PT x=1,5 va x=1

c, x^2+6x+10

=x^2+6x+9+1

=(x+3)^2+1

PT : (x+3)^2+1=0

Vay nghiem cua PT tren vo nghiem .

d, x^3-x^2-4x+4

=x^3-4x-x^2+4

=x(x^2-4)-(x^2-4)

=x(x-2)(x+2)-(x-2)(x+2)

=(x-2)(x+2)(x-1)

PT : (x-2)(x+2)(x-1)=0

Vay nghiem cua PT la :x=2;-2;1