Question

1. Phân tích đa thức thành nhân tử 

a) \(x^4+2x^3-4x-4\) 

 

b) \(a^2b+b^2c+c^2a+ab^2+bc^2+ca^2+3abc\)

2. Tìm x

a, \(3x^4-10x^2-8=0\)

b, \(x^39x^2+26x+24\)

Answer 1

a,x^4+2x^3-4x-4

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

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

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

Answer 2

\(X^4+2X^3-4X-4\)

\(=\left(X^2\right)^2+2X^3-4X-2^2\)

\(=\left[\left(X^2\right)^2-2^2\right]+\left[2X^3-4X\right]\)

\(=\left(X^2+2\right)\left(X^2-2\right)+2X\left(X^2-2\right)\)

\(=\left(X^2-2\right)\left(X^2+2+2X\right)\)