Question

phân tíchthành nhân tử

a/x^3+3x^2+6x+4

b/3a^2c^2+bd+3abc+acd

c/3a^2-6ab+3b^2-12c^2

d/x^2+y^2-x^2y^2+xy-x-y

e/a^6-b^6

Answer 1

\(x^3+3x^2+6x+4=\left(x^3+x^2\right)+\left(2x^2+2x\right)+\left(4x+4\right)\)

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

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

Answer 2

a)   \(x^3+3x^2+6x+4\)

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

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

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

b) \(3a^2c^2+bd+3abc+acd\)

\(=\left(3a^2c^2+acd\right)+\left(3abc+bd\right)\)

\(=ac\left(3ac+d\right)+b\left(3ac+d\right)\)

\(=\left(ac+b\right)\left(d+3ac\right)\)

Answer 3

c)  \(3a^2-6ab+3b^2-12c^2=3\left(a^2-2ab+b^2-4c^2\right)\)

\(=3\left[\left(a-b\right)^2-4c^2\right]=3\left(a-b-2c\right)\left(a-b+2c\right)\)

d) \(x^2+y^2-x^2y^2+xy-x-y\)

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

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

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

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

e)  \(a^6-b^6=\left(a^3-b^3\right)\left(a^3+b^3\right)=\left(a-b\right)\left(a^2+ab+b^2\right)\left(a+b\right)\left(a^2-ab+b^2\right)\)