a) \(ax^3-3ax^2+3ax-a\)

\(=a\left(x^3-1\right)-3ax\left(x-1\right)\)

\(=a\left(x-1\right)\left(x^2+x+1\right)-3ax\left(x-1\right)\)

\(=\left(x-1\right)\left(ax^2+ax+a-3ax\right)\)

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

\(x^2-a^2+2ab-b^2\)

\(=x^2-\left(a-b\right)^2\)

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

\(x^2-x-y^2-y\)

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

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

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

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

\(=\left(x-y\right)^2-z^2\)

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

a) \(xy+y^2+x+y\)

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

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

b) \(x^2-3x+xy-3y\)

\(=x\left(x-3\right)+y\left(x-3\right)\)

\(=\left(x+y\right)\left(x-3\right)\)

c) \(x^3-2x^2-3x+6\)

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

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

d) \(x^2+2xy+6y-9\)

\(=\left(x+3\right)\left(x-3\right)+2y\left(x+3\right)=\left(x+3\right)\left(x-2y+3\right)\)

chịu luôn

\(x^2\left(x-3\right)-4x+12\)

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

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

\(=\left(x+2\right)\left(x-2\right)\left(x-3\right)=0\)

B = x15 - 8x14 + 8x13 - 8x2 + ... - 8x2 + 8x - 5

B = x^15 - 7x^14 -x^14+7x^13+x^13-7x^12-...-x^2+7x+x-5

B = x^14(x-7) - x^14(x-7) +...+x^2(x-7)-x(x-7)+x-5

B = 7-5=2

khoooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong

mn tính hộ mik kq với

\(\left(2xy^3+4x^2y^2\right)\div xy\)

\(=xy\left(2y^2+4xy\right):xy\)

\(=2y^2+4xy\)