Question

phân tích đa thức thành nhân tử

a) 3abc³-6a²b³c+12a³bc

b) 27-8y³

c) 4x²+4x-y²+11

d) 3a²(x-2)-6ab(2-x)

Answer 1

a: \(3abc^3-6a^2b^3c+12a^3bc\)

\(=3abc\cdot c^2-3abc\cdot2ab^2+3abc\cdot4a^2\)

\(=3abc\left(c^2-2ab^2+4a^2\right)\)

b: \(27-8y^3\)

\(=3^3-\left(2y\right)^3\)

\(=\left(3-2y\right)\left(9+6y+4y^2\right)\)

c: Sửa đề: \(4x^2+4x-y^2+1\)

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

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

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

d: \(3a^2\cdot\left(x-2\right)-6ab\cdot\left(2-x\right)\)

\(=3a^2\cdot\left(x-2\right)+6ab\cdot\left(x-2\right)\)

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

\(=3a\left(a+2b\right)\left(x-2\right)\)