Question

Phân tích đa thức:

a) x^2-y^2+7x+7y

b) x^2+5x+4

c) x^3-9x^2

d) x^3+x^2+2x

e) 3x^2+3y^2-6xy-1^2

Answer 1

a)\(x^2-y^2+7x+7y\)

\(=\left(x-y\right).\left(x+y\right)+7.\left(x+y\right)\)

\(=\left(x+y\right).\left(x-y+7\right)\)

\(b,x^2+5x+4\)

\(=x^2+x+4x+4\)

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

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

\(c,x^3-9x^2\)

\(=x^2.\left(x-9\right)\)

\(d,x^3+x^2+2x\)

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

\(e,3x^2+3y^2-6xy-1^2\)

\(=\left(3x-3y\right)^2-1^2\)

\(=\left(3x-3y-1\right).\left(3x-3y+1\right)\)

Answer 2

cho sửa câu cuối cái nha :>

\(=3.\left(x-y\right)^2-1^{^2}\)

\(=3x^2-3y^2-1^2\)

đến đây tịt r :< sory