Question

Answer 1

2.a) pt

<=> 2(x-2)(x+1)=0

<=> x-2=0 hoặc x+1=0

<=> x=2 hoặc x=-1

b) pt 

<=> (x-3)(x^2+3)=0

<=> x-3=0 hoặc x^2 + 3=0 

<=> x=3 hoặc x^2=-3 (vô lí)

Vậy x=3

Answer 2

Bài 1: 

a: \(2x^3-6x^2+4\)

\(=2x^3-2x^2-4x^2+4\)

\(=2x^2\left(x-1\right)-4\left(x-1\right)\left(x+1\right)\)

\(=2\left(x-1\right)\left(x^2-2x-2\right)\)

b: \(3x^2y+2xy^2-xy\)

\(=xy\left(3x+2y-1\right)\)

c: \(\left(x-1\right)^2+\left(x-2\right)\left(x-1\right)\)

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

\(=\left(x-1\right)\left(2x-3\right)\)

Answer 3

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

b) = xy(3x+2y-1)

c) (x-1)(2x-3)

d) (x+1)(2x+5)

e) x^2+2x+2

Answer 4

3. A=(x+y)(x-y-2)

Khi x=2023; y=2021 thì x-y-2=0

--> A = 0