Question

Phân tích các đa thức sau thành nhân tử:

\(e,30x^3-18x^2y-72y+120x\)

\(f,70x-84y+20xy-24y^2\)

Answer 1

e, (30x³+120x)-(18x²y+72y)

=30x(x²+4)-18y(x²+4)

=(x²+4)(30x-18y)

f,(70x+20xy)-(84y+24y²)

= 10x(7+2y)-12y(7+2y)

=)7+2y)(10x-12y)

Answer 2

e) 30x³ - 18x²y - 72y +120x

= 6 ( 5x³ - 3x²y - 12y + 20x )

= 6 ( x² (5x - 3y) + 4 (5x - 3y)

= 6 (x²+4)(5x-3y)

Answer 3

f) 70x - 84y + 20xy -24y²

= 2 (35x - 42y + 10xy - 12y²)

= 2 ( 7(5x - 6y) + 2y(5x - 6y))

= 2(5x-6y)(7+2y)