Question

Bài 4. Phân tích các đa thức sau thành nhân tử:

a) 36x³ y³ - 42x² y²                      

b) 3x⁴ y² + 15x² y -18xy

c) ax - bx + ab - x²

d) 3(2x -1) - 4x² + 4x -1

Answer 1

a) \(=6x^2y^2\left(6xy-7\right)\)

b) \(=3xy\left(x^3y+5x-6\right)\)

c) \(=\left(ax+ab\right)-\left(bx+x^2\right)=a\left(b+x\right)-x\left(b+x\right)=\left(a-x\right)\left(b+x\right)\)

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

 

Answer 2

\(a,=6x^2y^2\left(6xy-7\right)\\ b,=3xy\left(x^3y+5x-6\right)\\ c,=x\left(a-x\right)-b\left(a-x\right)=\left(x-b\right)\left(a-x\right)\\ d,=3\left(2x-1\right)-\left(2x-1\right)^2=\left(2x-1\right)\left(3-2x+1\right)=2\left(2-x\right)\left(2x-1\right)\)