Question

Bài 1 .phân tích các đa thức sau :

a.\(z^2-\left(x-1\right)^2+2\left(x-1\right)\)

b.\(xz-yz-x^2+2xy-y^2\)

c.\(a^2x+aby-2abx-2b^2y\)

d.\(ab\left(x^2+y^2\right)+xy\left(a^2+b^2\right)\)

e.\(x^2+2xy+y^2-2x-2y+1\)

g.\(3x-3y+x^2-2xy+y^2\)

h.\(x^3-y^3-3x+3y\)

i.\(x^2-2xy+y^2-z^2\)

Bài 2: Tìm x, biết

a.\(x\left(2x-7\right)-4x+14=0\)

b.\(2x^3+3x^2+2x+3=0\)

Answer 1

Bài 1 :

\(e,x^2+2xy+y^2-2x-2y+1\)

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

Bài 2:

\(b,2x^3+3x^2+2x+3=0\)

\(\Leftrightarrow\left(2x^3+2x\right)+\left(3x^2+3\right)=0\)

\(\Leftrightarrow2x\left(x^2+1\right)+3\left(x^2+1\right)=0\)

\(\Leftrightarrow\left(x^2+1\right)\left(2x+3\right)=0\)

\(\Leftrightarrow2x+3=0\left(x^2+1>0\right)\)

\(\Leftrightarrow x=-\dfrac{3}{2}\)

Answer 2