Question

[Đặng Khánh Ngọc]

a) x^2+5x-6

b) 5x^2+5xy-x-y

c) 7x-6x^2-2

d) x^2+4x+3

e) 2x^2+3x-5

f) 16x-5x^2-3

giải chi tiết

Answer 1

[Phan Văn Hiếu]

\(x^2+5x-6=x^2-x+6x-6=x\left(x-1\right)+6\left(x-1\right)=\left(x+6\right)\left(x-1\right)\)

\(5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)=\left(5x-1\right)\left(x+y\right)\)

\(7x-6x^2-2=-\left(6x^2-7x+2\right)=-\left[\left(6x^2-3x\right)-\left(4x+2\right)\right]=-\left[3x\left(2x-1\right)-2\left(2x-1\right)\right]=-\left[\left(3x-2\right)\left(2x-1\right)\right]\)

Answer 2

[Phan Văn Hiếu]

d) \(x^2+4x+3=x^2+x+3x+3=x\left(x+1\right)+3\left(x+1\right)=\left(x+3\right)\left(x+1\right)\)