Question

1.Phân tích thành nhân tử (phương pháp tách 1 hạng tử thành nhiều hạng tử)

 a. 4x^2 + 4x - 3

b. 2x^2 + xy - y^2

c. x^2 + 9x - 22

d.3x^2 - 2xy - y^2

Answer 1

a) \(4x^2+4x-3\)

\(=4x^2-2x+6x-3\)

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

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

Answer 2

b) \(2x^2+xy-y^2\)

\(=2x^2+2xy-xy-y^2\)

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

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

Answer 3

c) \(x^2+9x-22\)

\(=x^2+11x-2x-22\)

\(=x\left(x+11\right)-2\left(x+11\right)\)

\(=\left(x-2\right)\left(x+11\right)\)

Answer 4

d) \(3x^2-2xy-y^2\)

\(=3x^2+xy-3xy-y^2\)

\(=x\left(3x+y\right)-y\left(3x+y\right)\)

\(=\left(x-y\right)\left(3x+y\right)\)

Answer 5

b)   \(=x^2-y^2+x^2+xy=\left(x+y\right)\left(x-y\right)+x\left(x+y\right)=\left(x+y\right)\left(2x-y\right)\)

c) = \(x^2-2x+11x-22=x\left(x-2\right)+11\left(x-2\right)=\left(x-2\right)\left(x+11\right)\)

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

                                     =  \(\left(x-y\right)\left(3x+y\right)\)

Answer 6

\(a,\text{ }4x^2+4x-3\)

\(=4x^2-2x+6x-3\)

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

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

Answer 7

Trả lời : 

\(a,\text{ }4x^2+4x-3\)

\(=4x^2-2x+6x-3\)

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

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

Answer 8

\(a,4x^2+4x-3\)

\(=4x^2-2x+6x-3\)

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

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

Answer 9

\(b,2x^2+xy-y^2\)

\(=2x^2+2xy-xy-y^2\)

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

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

Answer 10

\(c,x^2+9x-22\)

\(=x^2+11x-2x-22\)

\(=x\left(x+11\right)-2\left(x+11\right)\)

\(=\left(x-2\right)\left(x+11\right)\)

Answer 11

\(d,3x^2-2xy-y^2\)

\(=3x^2+xy-3xy-y^2\)

\(=x\left(3x+y\right)-y\left(3x+y\right)\)

\(=\left(x-y\right)\left(3x+y\right)\)